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Applesoft BASIC
(Applesoft BASIC)
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Line 1:
{{task|Data Structures}}
 
;Task:
Write a simple tool to track a small set of data.
 
The tool should have a commandline interface to enter at least two different values.
The tool should have a command-line interface to enter at least two different values.
 
The entered data should be stored in a structured format and saved to disk.
 
It does not matter what kind of data is being tracked.   It could be your CDa collection (CDs, yourcoins, friendsbaseball birthdayscards, orbooks), a diary, an electronic organizer (birthdays/anniversaries/phone numbers/addresses), etc.
 
 
You should track the following details:
Line 13 ⟶ 17:
* Other optional fields
 
<br>
The command should support the following [[Command-line arguments]] to run:
* Add a new entry
Line 19 ⟶ 24:
* Print all entries sorted by a date
 
<br>
The category may be realized as a tag or as structure (by making all entries in that category subitems)
 
The file format on disk should be human readable, but it need not be standardized. &nbsp; A natively available format that doesn't need an external library is preferred. &nbsp; Avoid developing your own format however if you can use an already existing one. &nbsp; If there is no existing format available, pick one of: [[JSON]], [[S-Expressions]], [[YAML]], or [[wp:Comparison_of_data_serialization_formats|others]].
:::* &nbsp; [[JSON]]
:::* &nbsp; [[S-Expressions]]
:::* &nbsp; [[YAML]]
:::* &nbsp; [[wp:Comparison_of_data_serialization_formats|others]]
 
 
;Related task:
* &nbsp; [[Take notes on the command line]]
<br><br>
 
=={{header|11l}}==
{{trans|Kotlin}}
 
<syntaxhighlight lang="11l">T Item
String name, date, category
 
F (name, date, category)
.name = name
.date = date
.category = category
 
F String()
R .name‘, ’(.date)‘, ’(.category)
 
V db_filename = ‘simdb.csv’
 
F load()
[Item] db
L(line) File(:db_filename).read().rtrim("\n").split("\n")
V item = line.split(‘, ’)
db.append(Item(item[0], item[1], item[2]))
R db
 
F store(item)
File(:db_filename, APPEND).write(String(item)"\n")
 
F printUsage()
print(|‘
Usage:
simdb cmd [categoryName]
add add item, followed by optional category
latest print last added item(s), followed by optional category
all print all
For instance: add "some item name" "some category name’)
 
F addItem(args)
I args.len < 2
printUsage()
R
 
V date = Time().strftime(‘%Y-%m-%d %H:%M:%S’)
V cat = I args.len == 3 {args[2]} E ‘none’
store(Item(args[1], date, cat))
 
F printLatest(a)
V db = load()
I db.empty
print(‘No entries in database.’)
R
 
I a.len == 2
L(item) reversed(db)
I item.category == a[1]
print(item)
L.break
L.was_no_break
print(‘There are no items for category '’a[1]‘'’)
E
print(db.last)
 
F printAll()
V db = load()
I db.empty
print(‘No entries in database.’)
R
 
L(item) db
print(item)
 
:start:
I :argv.len C 2..4
S :argv[1].lowercase()
‘add’
addItem(:argv[1..])
‘latest’
printLatest(:argv[1..])
‘all’
printAll()
E
printUsage()
E
printUsage()</syntaxhighlight>
 
{{out}}
The same as in Kotlin.
 
=={{header|BASIC}}==
==={{header|Applesoft BASIC}}===
This program relies on DOS 3.3 to read and write the simple database as a text file on disk. Running the program with no options displays help on how to run the program with the various options.
<syntaxhighlight lang="gwbasic"> 10 FOR I = 0 TO 255:C = PEEK (512 + I):EOL = C = 0 OR C = 141: IF NOT EOL THEN C$ = C$ + CHR$ (C): NEXT I: STOP
20 DOS = (C = 141) * 128:AC = 0: FOR C = I - 1 TO 0 STEP - 1: IF PEEK (512 + C) = ASC (",") + DOS THEN AC = AC + 1: NEXT C
30 D$ = CHR$ (4):M$ = CHR$ (13): READ P$,C$(1),C$(2),C$(3),C$(4):F$ = P$ + ".TXT": ON AC GOTO 100,40,40,40: GOTO 500USAGE
40 C = 0: PRINT D$"OPEN "F$: PRINT D$"READ "F$
50 ONERR GOTO 80
60 INPUT "";NA$,GE$,DA$
70 C = C + 1: GOTO 60
80 POKE 216,0: IF PEEK (222) = 5 THEN PRINT D$"CLOSE "F$: ON AC GOTO 100,200,300,400
90 RESUME
 
REM ADD
100 PRINT M$C$(AC)M$
110 INPUT " NAME: ";NAME$
120 INPUT " GENRE: ";GENRE$
130 INPUT "DATE YYYY-MM-DD: ";DA$
140 PRINT D$"OPEN "F$: PRINT D$"APPEND "F$: PRINT D$"WRITE "F$: PRINT NAME$","GENRE$","DA$: PRINT D$"CLOSE "F$
150 GOTO 600"DONE
 
REM LATEST
200 PRINT M$C$(AC)M$M$" NAME: "NA$M$"GENRE: "GE$M$" DATE: "DA$;
210 GOTO 600"DONE
 
REM LATEST OF EACH GENRE
300 DIM NA$(C),GE$(C),DA$(C):GC = 0: PRINT D$"OPEN "F$: PRINT D$"READ "F$: FOR I = 1 TO C: GOSUB 350:NA$(J) = NA$:GE$(J) = GE$:DA$(J) = DA$: NEXT I: PRINT D$"CLOSE "F$
310 PRINT M$C$(AC)M$: FOR I = 1 TO GC: PRINT M$NA$(I)","GE$(I)","DA$(I);: NEXT I
320 GOTO 600"DONE
350 INPUT "";NA$,GE$,DA$: FOR J = 1 TO GC: IF GE$ = GE$(J) THEN RETURN
360 NEXT J:GC = GC + 1:J = GC: RETURN
 
REM ALL SORTED BY DATE
400 DIM NA$(C),GE$(C),DA$(C),DA(C):DC = 0: PRINT D$"OPEN "F$: PRINT D$"READ "F$: FOR I = 1 TO C: GOSUB 450:NA$(DC) = NA$:GE$(DC) = GE$:DA$(DC) = DA$:DA(DC) = DA(DP):DA(DP) = DC: NEXT I: PRINT D$"CLOSE "F$
410 PRINT M$C$(AC)M$:DA = DA(0): FOR I = 1 TO DC: PRINT M$NA$(DA)","GE$(DA)","DA$(DA);:DA = DA(DA): NEXT I
420 GOTO 600"DONE
450 DP = 0: INPUT "";NA$,GE$,DA$: IF NOT DC THEN DC = 1: RETURN
460 FOR J = 1 TO DC:DA = DA(DP): IF DA$ > DA$(DA) THEN DP = DA:DA = DA(DA): NEXT J:DA = DP
470 DC = DC + 1: RETURN
 
REM USAGE
500 DATA "SIMPLE DATABASE"
510 DATA " RUN: , ADD A NEW ENTRY"
520 DATA " RUN: ,, PRINT THE LATEST ENTRY"
530 DATA " RUN: ,,, LATEST OF EACH GENRE"
540 DATA " RUN: ,,,, ALL SORTED BY DATE"
550 IF NOT DOS THEN C$ = "RUN " + P$
560 PRINT "USAGE:"M$" "C$" ,..."M$" OR";: FOR I = 1 TO 4: PRINT M$C$(I);: NEXT I
 
REM DONE
600 END</syntaxhighlight>
==={{header|Run BASIC}}===
<syntaxhighlight lang="runbasic">sqliteconnect #sql, "f:\client.db" ' Connect to the DB
 
' -------------------------------
' show user options
' -------------------------------
[sho]
cls ' clear screen
button #acd, "Add a new entry", [add]
button #acd, "Print the latest entry", [last]
button #acd, "Print the latest entry for each category", [lastCat]
button #acd, "Print all entries sorted by a date", [date]
button #ex, "Exit", [exit]
wait
 
' ------------------------------------
' add a new entry (user input screen)
' ------------------------------------
[add]
cls ' clear the screen
html "<TABLE BORDER=1 CELLPADDING=0 CELLSPACING=0 bgcolor=wheat>"
html "<TR align=center BGCOLOR=tan><TD colspan=2>Client Maintenance</TD></TR><TR>"
html "<TD bgcolor=tan align=right>Client Num</TD><TD>"
textbox #clientNum,clientNum$,5
 
html "</TD></TR><TR><TD bgcolor=tan align=right>Name</TD><TD>"
textbox #name,name$,30
 
html "</TD></TR><TR><TD bgcolor=tan align=right>Client Date</TD><TD>"
textbox #clientDate,clientDate$,19
 
html "</TD></TR><TR><TD bgcolor=tan align=right>Category</TD><TD>"
textbox #category,category$,10
 
html "</TD></TR><TR><TR bgcolor=tan><TD colspan=2 ALIGN=CENTER>"
button #acd, "Add", [addIt]
button #ex, "Exit", [sho]
html "</TD></TR></TABLE>"
wait
 
' ---------------------------------------------
' Get data from the screen
' ---------------------------------------------
[addIt]
clientNum = #clientNum contents$()
name$ = trim$(#name contents$())
clientDate$ = trim$(#clientDate contents$())
category$ = trim$(#category contents$())
dbVals$ = clientNum;",'";name$;"','";clientDate$;"','";category$;"'"
sql$ = "INSERT into client VALUES ("; dbVals$ ; ")"
#sql execute(sql$)
goto [sho]
 
' ------------------------------------
' Select last entry
' ------------------------------------
[last]
sql$ = "SELECT *,client.rowid as rowid FROM client ORDER BY rowid desc LIMIT 1"
what$ = "---- Last Entry ----"
goto [shoQuery]
 
' ------------------------------------
' Select by category (Last date only)
' ------------------------------------
[lastCat]
sql$ = "SELECT * FROM client
WHERE client.clientDate = (SELECT max(c.clientDate)
FROM client as c WHERE c.category = client.category)
ORDER BY category"
what$ = "---- Last Category Sequence ----"
goto [shoQuery]
 
' ------------------------------------
' Select by date
' ------------------------------------
[date]
sql$ = "SELECT * FROM client ORDER BY clientDate"
what$ = "---- By Date ----"
 
[shoQuery]
cls
print what$
html "<TABLE BORDER=1 CELLPADDING=0 CELLSPACING=0>"
html "<TR align=center bgcolor=wheat><TD>Client<br>Num</TD><TD>Name</TD><TD>Client<br>Date</TD><TD>Category</TD></TR>" ' heading
#sql execute(sql$)
WHILE #sql hasanswer()
#row = #sql #nextrow()
clientNum = #row clientNum()
name$ = #row name$()
clientDate$ = #row clientDate$()
category$ = #row category$()
 
html "<TR><TD align=right>";clientNum;"</TD><TD>";name$;"</TD><TD>";clientDate$;"</TD><TD>";category$;"</TD></TR>"
WEND
html "</TABLE>"
button #c, "Continue", [sho]
wait
 
' ------ the end -------
[exit]
end</syntaxhighlight>
Output:
 
---- User Input ----<br />
<TABLE BORDER=1 CELLPADDING=0 CELLSPACING=0 bgcolor=wheat>
<TR align=center BGCOLOR=tan><TD colspan=2>Client Maintenance</TD></TR>
<TR><TD bgcolor=tan align=right>Client Num</TD><TD>5</TD></TR>
<TR><TD bgcolor=tan align=right>Name</TD><TD>Dawnridge Winery</TD></TR>
<TR><TD bgcolor=tan align=right>Client Date</TD><TD>2008-06-18 22:16</TD></TR>
<TR><TD bgcolor=tan align=right>Category</TD><TD>wine</TD></TR>
<TR><TR bgcolor=tan><TD colspan=2 ALIGN=CENTER>[Add] [Exit]</TD></TR></TABLE>
 
---- Last Entry ----<br />
<TABLE BORDER=1 CELLPADDING=0 CELLSPACING=0>
<TR align=center bgcolor=wheat><TD>Client<br>Num</TD><TD>Name</TD><TD>Client<br>Date</TD><TD>Category</TD></TR>
<TR><TD align=right>5</TD><TD>Dawnridge Winery</TD><TD>2008-06-18 22:16</TD><TD>wine</TD></TR></TABLE>
 
---- Last category Sequence ----<br />
<TABLE BORDER=1 CELLPADDING=0 CELLSPACING=0>
<TR align=center bgcolor=wheat><TD>Client<br>Num</TD><TD>Name</TD><TD>Client<br>Date</TD><TD>Category</TD></TR>
<TR><TD align=right>1</TD><TD>Home Sales</TD><TD>2012-01-01 10;20</TD><TD>broker</TD></TR>
<TR><TD align=right>4</TD><TD>Back 40 Equipment</TD><TD>2009-09-18 20:18</TD><TD>farm</TD></TR>
<TR><TD align=right>3</TD><TD>Floral Designs</TD><TD>2010-10-14 09:16</TD><TD>flowers</TD></TR>
<TR><TD align=right>2</TD><TD>Best Foods</TD><TD>2011-02-02 12:33</TD><TD>food</TD></TR>
<TR><TD align=right>5</TD><TD>Dawnridge Winery</TD><TD>2008-06-18 22:16</TD><TD>wine</TD></TR></TABLE>
 
---- Date Sequence ----<br />
<TABLE BORDER=1 CELLPADDING=0 CELLSPACING=0>
<TR align=center bgcolor=wheat><TD>Client<br>Num</TD><TD>Name</TD><TD>Client<br>Date</TD><TD>Category</TD></TR>
<TR><TD align=right>5</TD><TD>Dawnridge Winery</TD><TD>2008-06-18 22;16</TD><TD>wine</TD></TR>
<TR><TD align=right>4</TD><TD>Back 40 Equipment</TD><TD>2009-09-18 20:18</TD><TD>farm</TD></TR>
<TR><TD align=right>3</TD><TD>Floral Designs</TD><TD>2010-10-14 09:16</TD><TD>flowers</TD></TR>
<TR><TD align=right>2</TD><TD>Best Foods</TD><TD>2011-02-02 12:33</TD><TD>food</TD></TR>
<TR><TD align=right>1</TD><TD>Home Sales</TD><TD>2012-01-01 10:20</TD><TD>broker</TD></TR></TABLE>
 
=={{header|Bracmat}}==
This is a rather minimal solution. The program is run from the command line of the operating system, in this example the Windows command prompt. The program is stored in a file called 'sdb':
<syntaxhighlight lang="bracmat"> whl
' ( arg$:?command
& ( get'db
| (db=1)&lst$(db,db,NEW)
)
& !command
: ( add
& :?name:?tag:?date
& whl
' ( arg$:?argmnt
& arg$:?value
& (!argmnt.!value)
: ( (title|name.?name)
| (category|tag.?tag)
| (date.?date)
)
)
& ( !name:~
& !tag:~
& !date:~
& ( !db:?*!tag^(?+(!date.!name)+?)*?
& out$"This record already exists"
| !tag^(!date.!name)*!db:?db
& lst$(db,db,NEW)
)
| out$"invalid data"
)
| latest
& :?date
& nothing found:?latest
& ( !db
: ?
* ?tag
^ ( ?
+ ( (>!date:?date.?name)
& (!name,!tag,!date):?latest
& ~
)
+ ?
)
* ?
| out$!latest
)
| latest/category
& :?date:?latests:?latest
& ( !db
: ?
* ( ?tag
& !latests !latest:?latests
& :?latest:?date
)
^ ( ?
+ ( (>!date:?date.?name)
& (!name,!tag,!date):?latest
& ~
)
+ ?
)
* ?
| !latests !latest:?latests&out$!latests
)
| sorted
& 0:?sorted
& ( !db
: ?
* ?tag
^ ( ?
+ ( (?date.?name)
& (!date.!name,!tag,!date)+!sorted:?sorted
& ~
)
+ ?
)
* ?
| whl
' (!sorted:(?.?row)+?sorted&out$!row)
)
)
);
</syntaxhighlight>
First we add some records, a some ships that arrived at the harbour in Rotterdam today.
<pre>bracmat "get$sdb" add name "CORONA BULKER" tag "BULK CARRIER" date "2014.10.21.04:00"
bracmat "get$sdb" add name "FPMC 21" tag "CHEMICAL TANKER" date "2014.10.15.12:00"
bracmat "get$sdb" add name "CHINA PROGRESS" tag "BULK CARRIER" date "2014.10.13.22:00"
bracmat "get$sdb" add name "FAIRCHEM YUKA" tag "CHEMICAL TANKER" date "2014.10.13.12:00"
bracmat "get$sdb" add name "NAVE COSMOS" tag "CHEMICAL TANKER" date "2014.10.13.10:00"
bracmat "get$sdb" add name "GOLDEN ICE" tag "BULK CARRIER" date "2014.10.10.12:00"
bracmat "get$sdb" add name "GHAZAL" tag "CRUDE OIL" date "2014.10.10.12:00"
bracmat "get$sdb" add name "HS MEDEA" tag "CRUDE OIL" date "2014.10.10.02:00"</pre>
Instead of 'name' you can use 'title' and instead of 'tag' you can use 'category'. The date has to be year first and day last, followed by time information if you like. No attempt is made to validate the date/time. Now the queries:
<pre>prompt> bracmat "get$sdb" latest
CORONA BULKER,BULK CARRIER,2014.10.21.04:00
 
prompt> bracmat "get$sdb" latest/category
(CORONA BULKER,BULK CARRIER,2014.10.21.04:00)
(FPMC 21,CHEMICAL TANKER,2014.10.15.12:00)
(GHAZAL,CRUDE OIL,2014.10.10.12:00)
 
prompt> bracmat "get$sdb" sorted
HS MEDEA,CRUDE OIL,2014.10.10.02:00
GHAZAL,CRUDE OIL,2014.10.10.12:00
GOLDEN ICE,BULK CARRIER,2014.10.10.12:00
NAVE COSMOS,CHEMICAL TANKER,2014.10.13.10:00
FAIRCHEM YUKA,CHEMICAL TANKER,2014.10.13.12:00
CHINA PROGRESS,BULK CARRIER,2014.10.13.22:00
FPMC 21,CHEMICAL TANKER,2014.10.15.12:00
CORONA BULKER,BULK CARRIER,2014.10.21.04:00</pre>
 
The database file 'db' looks like this:
<pre>db= "BULK CARRIER"
^ ( ("2014.10.10.12:00"."GOLDEN ICE")
+ ("2014.10.13.22:00"."CHINA PROGRESS")
+ ("2014.10.21.04:00"."CORONA BULKER")
)
* "CHEMICAL TANKER"
^ ( ("2014.10.13.10:00"."NAVE COSMOS")
+ ("2014.10.13.12:00"."FAIRCHEM YUKA")
+ ("2014.10.15.12:00"."FPMC 21")
)
* "CRUDE OIL"^(("2014.10.10.02:00"."HS MEDEA")+("2014.10.10.12:00".GHAZAL));</pre>
 
Use is made of Bracmat's automatic normalization of algebraic formula to turn the data into a hierarchical structure, with the tag as the top level and the date/time immediately below that level.
See also [[Take notes on the command line]] for a related task.
 
=={{header|C}}==
Line 34 ⟶ 444:
"Treasure Beach","Argus","Jemky","09-22-1999","Lancast"
 
<langsyntaxhighlight Clang="c">#include <stdio.h>
#include <stdlib.h> /* malloc */
#include <string.h> /* strlen */
Line 45 ⟶ 455:
#define FREE(a) if(a) {free(a);a=NULL;}
#define sort_by(foo) \
static int by_##foo (pdb_tconst void*p1, pdb_tconst void*p2) { \
return strcmp ((*(const pdb_t*)p1)->foo, (*(const pdb_t*)p2)->foo); }
typedef struct db {
char title[26];
Line 56 ⟶ 466:
}
db_t,*pdb_t;
typedef int (sort)(pdb_tconst void*, pdb_tconst void*);
typedef int (*compfn)(const void*, const void*);
enum {CREATE,PRINT,TITLE,DATE,AUTH,READLINE,READ,SORT,DESTROY};
static pdb_t dao (int cmd, FILE *f, pdb_t db, sort sortby);
Line 65 ⟶ 474:
sort_by(last_name);
sort_by(title);
static sortint by_date(pdb_t *p1, pdb_t *p2);
/* main */
int main (int argc, char **argv) {
char buf[100], *commands[]={"-c", "-p", "-t", "-d", "-a", NULL};
const char *commands[]={"-c", "-p", "-t", "-d", "-a", NULL};
db_t db;
db.next=NULL;
Line 76 ⟶ 486:
TRY (f=fopen(DB,"a+"));
if (argc<2) {
usage: printf ("Usage: %s [commands]\n"
"-c Create new entry.\n"
"-p Print the latest entry.\n"
"-t Print all entries sorted by title.\n"
"-d Print all entries sorted by date.\n"
"-a Print all entries sorted by author.\n",argv[0]);
fclose (f);
Line 112 ⟶ 522:
printf ("-d Print all entries sorted by date.\n");
dblist = dao (READ,f,&db,NULL);
dblist = dao (SORT,f,dblist,(int (*)(const void *,const void *)) by_date);
dao (PRINT,f,dblist,NULL);
dao (DESTROY,f,dblist,NULL);
Line 189 ⟶ 599:
in_db=in_db->next;
}
qsort (pdb,i,sizeof in_db,(compfn)sortby);
pdb[i-1]->next=NULL;
for (i=i-1;i;i--) {
pdb[i-1]->next=pdb[i];
}
Line 226 ⟶ 636:
}
else return ((*p1)->date > (*p2)->date);
}</langsyntaxhighlight>
 
=={{header|CommonC Lispsharp|C#}}==
<syntaxhighlight lang="c sharp">
A tool to track the episodes you have watched in a series.
using System;
Tested with [[SBCL]] but should work with other implementations.
using System.IO;
 
namespace Simple_database
Run from the commandline as:
{
sbcl --script watch.lisp
class Program
{
public static void Main(string[] args)
{
//
// For appropriate use of this program
// use standard Windows Command Processor or cmd.exe
//
// Create cmd.bat file at the same folder with executive version
// of program Simple_database.exe, so when started, the correct
// file path will be automatically set to cmd console.
//
// Start notepad, write only cmd.exe and save file as cmd.bat
//
// To start cmd just double click at cmd.bat file.
//
//
//
// Console application command line start command
//
// application name.exe [argument] [argument parameters]
//
//
// Command line argument followed by parameters
//
// [a] - Add new entry
//
// ["data1"]["data2"]["data3"]...["data n"]
//
// ["data1"] - Data category !
// ["data2"] - Data
// ["data3"] - Data
//
//
// NOTICE !
//
// First parameter is taken for data category.
//
//
//
// Command line argument with no parameters
//
// [p1] - Print the latest entry
//
// [p2] - Print the latest entry for each category
//
// [p3] - Print all entries sorted by a date
//
//
//
//
// Command line example
//
// Small_database.exe [a] ["home"] ["+398125465458"] ["My tel number"]
//
// Small_database.exe [a] ["office"] ["+398222789000"] ["Boss"]
//
// Small_database.exe [a] [cd] ["Action movie"] ["Movie title"]
// Small_database.exe [a] [cd] ["SF movie"] ["Movie title"]
// Small_database.exe [a] [dvd] ["Action movie"] ["Movie title"]
//
//
// NOTICE !
//
// Brackets and space between arguments and parameters are necessary.
// Quotes must be used when parameters have more than one word.
//
// If not used as shown in examples, program will show error message.
//
//
//
// Check command line for arguments
//
//
if(args.Length==0)
{
Console.WriteLine();
Console.WriteLine(" Missing Argument Error. ");
Console.WriteLine();
}
else
{
switch (args[0])
{
case "[a]" : Add_New_Entry(args);
break;
case "[p1]": Print_Document("Print the latest entry.txt");
break;
case "[p2]": Print_Document("Print the latest entry for each category.txt");
break;
case "[p3]": Print_Document("Print all entries sorted by a date.txt");
break;
default :
{
Console.WriteLine();
Console.WriteLine(" Incorrect Argument Error. ");
Console.WriteLine();
}
break;
}
}
}
static void Add_New_Entry(string [] args)
{
//
// Check parameters
//
//
// Minimum one parameter, category
//
if(args.Length==1)
{
Console.WriteLine();
Console.WriteLine(" Missing Parameters Error..... ");
Console.WriteLine();
}
else
{
bool parameters_ok = true;
foreach (string a in args)
{
if(!a.StartsWith("[") || !a.EndsWith("]"))
{
parameters_ok = !parameters_ok;
break;
}
}
//
// Add new entry to Data base document
//
if(parameters_ok)
{
//
//
//
Console.WriteLine();
Console.WriteLine(" Parameters are ok..... ");
Console.WriteLine();
Console.WriteLine(" Writing new entry to database..... ");
//
// Create new Data base entry
//
args[0] = string.Empty;
string line = string.Empty;
foreach (string a in args)
{
line+=a;
}
line+="[" + DateTime.Now.ToString() + "]";
args[0] = "[" + DateTime.Now.ToString() + "]";
//
// Write entry to Data base
//
StreamWriter w = new StreamWriter("Data base.txt",true);
w.WriteLine(line);
//
// Close and dispose stream writer
//
w.Close();
w.Dispose();
//
//
//
Console.WriteLine();
Console.WriteLine(" New entry is written to database. ");
 
Create_Print_Documents(args);
Without arguments the function <code>(watch-list)</code> is invoked to show the last episode of each series.
With the argument <code>add</code> the function <code>(watch-add)</code> will allow you to add a new episode with series name, episode title, episode number and date watched. If the series does not yet exist, you will be asked if you want to create it.
//
//
//
Console.WriteLine();
Console.WriteLine(" Add new entry command executed. ");
//
//
//
}
else
{
Console.WriteLine();
Console.WriteLine(" ! Parameters are not ok ! ");
Console.WriteLine();
Console.WriteLine(" Add new entry command is not executed. ");
Console.WriteLine();
}
}
}
static void Create_Print_Documents(string [] args)
{
//
//
//
Console.WriteLine();
Console.WriteLine(" Creating new print documents. ");
//
// Create "Print all entries sorted by a date.txt"
//
File.Copy("Data base.txt","Print all entries sorted by a date.txt",true);
//
//
//
Console.WriteLine();
Console.WriteLine(" Print all entries sorted by a date.txt created. ");
//
// Create "Print the latest entry.txt"
//
//
// Create new entry
//
string line = string.Empty;
foreach (string a in args)
{
line+=a;
}
//
StreamWriter w = new StreamWriter("Print the latest entry.txt");
//
w.WriteLine(line);
//
w.Close();
w.Dispose();
//
//
//
Console.WriteLine();
Console.WriteLine(" Print the latest entry.txt created. ");
//
// Create "Print the latest entry for each category.txt"
//
string latest_entry = string.Empty;
foreach (string a in args)
{
latest_entry+=a;
}
if(!File.Exists("Print the latest entry for each category.txt"))
{
File.WriteAllText("Print the latest entry for each category.txt",latest_entry);
}
else
{
StreamReader r = new StreamReader("Print the latest entry for each category.txt");
//
w = new StreamWriter("Print the latest entry for each category 1.txt",true);
//
line = string.Empty;
//
while(!r.EndOfStream)
{
line = r.ReadLine();
if(line.Contains(args[1].ToString()))
{
w.WriteLine(latest_entry);
latest_entry = "ok";
}
else
{
w.WriteLine(line);
}
}
// add new category
if(latest_entry != "ok")
w.WriteLine(latest_entry);
//
w.Close();
w.Dispose();
//
r.Close();
r.Dispose();
//
File.Copy("Print the latest entry for each category 1.txt",
"Print the latest entry for each category.txt",true);
//
File.Delete("Print the latest entry for each category 1.txt");
//
//
//
Console.WriteLine();
Console.WriteLine(" Print the latest entry for each category.txt created. ");
Console.WriteLine();
}
}
static void Print_Document(string file_name)
{
//
// Print document
//
Console.WriteLine();
Console.WriteLine(file_name.Replace(".txt","")+ " : ");
Console.WriteLine();
//
StreamReader r = new StreamReader(file_name);
//
string line = string.Empty;
//
line = r.ReadToEnd();
//
Console.WriteLine(line);
//
r.Close();
r.Dispose();
//
//
//
}
}
}
</syntaxhighlight>
{{out| Program Input and Output}}
<pre>
Data base can be filled by creating cmd.bat file with following contents:
</pre>
<pre>
Simple_database.exe [a] [cd] ["Action"] ["Movie name"]
Simple_database.exe [a] [cd] ["Fiction"] ["Movie name"]
Simple_database.exe [a] [cd] ["Drama"] ["Movie name"]
Simple_database.exe [a] [cd] ["SF"] ["Movie name"]
Simple_database.exe [a] [cd] ["Comedy"] ["Movie name"]
Simple_database.exe [a] [cd] ["Horor"] ["Movie name"]
 
Simple_database.exe [a] [dvd] ["Action"] ["Movie name"] ["Fiction"] ["Movie name"]
This code is also available under the GNU GPLv3.
Simple_database.exe [a] [dvd] ["SF"] ["Movie name"] ["SF"] ["Movie name"]
<lang lisp>(defvar *db* nil)
Simple_database.exe [a] [dvd] ["Drama"] ["Movie name"] ["Action"] ["Movie name"]
Simple_database.exe [a] [dvd] ["Comedy"] ["Movie name"] ["SF"] ["Movie name"]
Simple_database.exe [a] [dvd] ["Horor"] ["Movie name"] ["Fiction"] ["Movie name"]
 
pause
(defstruct series description tags episodes)
</pre>
<pre>
When data base is formed use start command with parameters for data base query:
 
C:\PROJECTS\Roseta\Simple database\Simple database\bin\Debug>Simple_database.exe [p2]
(defstruct (episode (:print-function print-episode-struct))
series title season episode part date tags)
 
And the result is
(defun format-ymd (date)
</pre>
(format nil "~{~a.~a.~a~}" date))
<pre>
Print the latest entry for each category :
 
[28.3.2018 15:06:18][cd][Horor][Movie name]
(defun print-episode-struct (ep stream level)
[28.3.2018 15:06:18][dvd][Horor][Movie name][Fiction][Movie name]
(let ((*print-pretty* nil))
</pre>
(format stream (if *print-escape*
"#s(episode~@{~*~@[ :~1:*~a ~s~]~})"
"~&~34< ~*~a~;~*~@[~d-~]~*~d~> ~45<~*~@[~a ~]~*~@[(~a) ~]~;~*~@[(~a)~]~>~*~@[ (~{~a~^ ~})~]")
:series (episode-series ep)
:season (episode-season ep)
:episode (episode-episode ep)
:title (episode-title ep)
:part (episode-part ep)
:date (if *print-escape*
(episode-date ep)
(when (episode-date ep)
(format-ymd (episode-date ep))))
:tags (episode-tags ep))))
 
=={{header|COBOL}}==
(defun get-value (key alist)
This is a souped-up version of the task from [[Take notes on the command line]]. It stores the current date, a tag, a title and a note as an entry in a file. The database produced is not particularly human-readable or easy to modify, but it is in a well-structured format.
(cdr (assoc key alist)))
{{works with|OpenCOBOL}}
<syntaxhighlight lang="cobol"> IDENTIFICATION DIVISION.
PROGRAM-ID. simple-database.
 
ENVIRONMENT DIVISION.
INPUT-OUTPUT SECTION.
FILE-CONTROL.
SELECT OPTIONAL database-file ASSIGN Database-Path
ORGANIZATION INDEXED
ACCESS SEQUENTIAL
RECORD KEY data-title
ALTERNATE RECORD KEY data-tag
WITH DUPLICATES
ALTERNATE RECORD KEY date-added
WITH DUPLICATES
FILE STATUS file-status
.
DATA DIVISION.
FILE SECTION.
FD database-file.
01 database-record.
*> Date is in YYYYMMDD format.
03 date-added PIC 9(8).
03 data-tag PIC X(20).
03 data-title PIC X(50).
03 data-contents PIC X(200).
*> Adding extra space is considered good style so the record
*> can be expanded in the future.
03 FILLER PIC X(50).
 
WORKING-STORAGE SECTION.
(defun get-latest (database)
78 Database-Path VALUE "database.dat".
(when database
(cons (car (series-episodes (cdar database))) (get-latest (cdr database)))))
 
01 file-status PIC XX.
(defun get-all (database)
88 file-ok VALUE "00".
(when database
88 duplicate-key VALUE "22".
(append (series-episodes (cdar database)) (get-all (cdr database)))))
88 key-not-found VALUE "23".
 
01 num-args PIC 99.
(defun compare-date (a b)
(cond ((not a) t)
((not b) nil)
((= (first a) (first b))
(compare-date (rest a) (rest b)))
(t (< (first a) (first b)))))
 
01 action PIC XX.
(defun compare-by-date (a b)
88 create-entry VALUE "-c".
(compare-date (episode-date a) (episode-date b)))
88 remove-entry VALUE "-r".
88 find-entry VALUE "-f".
88 print-latest VALUE "-l".
88 print-database VALUES "-a", "-d", "-t".
*> Printed by title.
88 print-by-title VALUE "-a".
88 print-by-date VALUE "-d".
88 print-by-tag VALUE "-t".
88 print-help VALUES "-h", SPACES.
 
01 read-direction-flag PIC X VALUE SPACE.
(defun prompt-read (prompt &optional default)
88 read-backwards VALUE "B".
(format *query-io* "~a~@[ (~a)~]: " prompt default)
(force-output *query-io*)
(let ((answer (read-line *query-io*)))
(if (string= answer "")
default
answer)))
 
01 edited-date PIC 9(4)/99/99.
(defun split (seperator string)
(loop for i = 0 thenPROCEDURE (1+ j)DIVISION.
DECLARATIVES.
as j = (search seperator string :start2 i)
database-file-error SECTION.
collect (subseq string i j)
USE AFTER ERROR ON database-file
while j))
 
DISPLAY "An error has occurred while using " Database-Path
(defun get-current-date ()
". Error no. " file-status
(multiple-value-bind
DISPLAY "The program will terminate."
(second minute hour date month year day-of-week dst-p tz)
(get-decoded-time)
(declare (ignore second minute hour day-of-week dst-p tz))
(list date month year)))
 
CLOSE database-file
 
GOBACK
(defun parse-date (date)
.
(reverse (mapcar #'parse-integer (split "." date))))
END DECLARATIVES.
 
main-line.
(defun parse-tags (tags)
DISPLAY 1 UPON ARGUMENT-NUMBER
(when (and tags (string-not-equal "" tags))
ACCEPT action FROM ARGUMENT-VALUE
(mapcar #'intern (split " " (string-upcase tags)))))
 
ACCEPT num-args FROM ARGUMENT-NUMBER
(defun parse-number (number)
(if (stringp number)
(parse-integer number :junk-allowed t)
number))
 
EVALUATE TRUE
(defun prompt-for-episode (&optional last)
WHEN create-entry
(when (not last)
(setf last (make IF num-episode)))args >= 4
PERFORM write-entry
(make-episode
ELSE
:series (prompt-read "Series Title" (episode-series last))
DISPLAY "-a requires arguments to enter in the "
:title (prompt-read "Title")
"database. See help (-h) for details."
:season (parse-number (prompt-read "Season" (episode-season last)))
END-IF
:episode (parse-number (prompt-read "Episode" (1+ (or (episode-episode last) 0))))
:part (parse-number (prompt-read "Part" (when (episode-part last)
(1+ (episode-part last)))))
:date (parse-date (prompt-read "Date watched" (format-ymd (get-current-date))))
:tags (parse-tags (prompt-read "Tags"))))
 
WHEN remove-entry
(defun parse-integer-quietly (&rest args)
IF num-args >= 2
(ignore-errors (apply #'parse-integer args)))
PERFORM delete-entry
ELSE
DISPLAY "-r requires the title of the entry to "
"delete."
END-IF
 
WHEN find-entry
(defun get-next-version (basename)
IF num-args >= 2
(flet ((parse-version (pathname)
PERFORM (or (parsedisplay-integerspecified-quietly entry
(string-left-trim (file-namestring basename) ELSE
DISPLAY "-f requires the title of the entry to (file-namestring pathname))"
:start 1) 0)))"find."
END-IF
(let* ((files (directory (format nil "~A,*" (namestring basename))))
(max (if files
(reduce #'max files :key #'parse-version)
0)))
(merge-pathnames (format nil "~a,~d" (file-namestring basename) (1+ max))
basename))))
 
WHEN print-latest
(defun save-db (dbfile database)
PERFORM show-latest
(let ((file (probe-file dbfile)))
(rename-file file (get-next-version file))
(with-open-file (out file :direction :output)
(with-standard-io-syntax
(let ((*print-case* :downcase))
(pprint database out))))))
 
WHEN print-database
(defun watch-save (dbfile)
PERFORM show-database
(save-db dbfile *db*))
 
WHEN print-help
(defun load-db (dbfile)
PERFORM show-general-help
(with-open-file (in dbfile)
(with-standard-io-syntax
(read in))))
 
WHEN OTHER
(defun get-series (name database)
DISPLAY action " is not a valid option."
(cdr (assoc name database :test #'equal)))
END-EVALUATE
GOBACK
.
write-entry.
OPEN EXTEND database-file
 
DISPLAY 2 UPON ARGUMENT-NUMBER
(defun get-episode-list (series database)
ACCEPT data-tag FROM ARGUMENT-VALUE
(series-episodes (get-series series database)))
DISPLAY 3 UPON ARGUMENT-NUMBER
ACCEPT data-title FROM ARGUMENT-VALUE
IF data-title = SPACES
DISPLAY "The title cannot be blank."
PERFORM close-and-terminate
END-IF
 
DISPLAY 4 UPON ARGUMENT-NUMBER
(defun print-series (series)
ACCEPT data-contents FROM ARGUMENT-VALUE
(format t "~30a ~a ~@[ (~{~a~^ ~})~]~%"
(car series) (series-description (cdr series)) (series-tags (cdr series)))
(format t "~{~a~%~}" (series-episodes series)))
 
ACCEPT date-added FROM DATE YYYYMMDD
(defun watch-series (title)
(let ((series (get-series title *db*)))
(format t "~30a ~@[ (~{~a~^ ~})~]~%~@[ ~a~%~]" title (series-tags series)
(series-description series))
(format t "~{~a~%~}" (reverse (series-episodes series)))))
 
(defun dump-db ( WRITE database)-record
INVALID KEY
(dolist (series database)
IF duplicate-key
(print-series (cdr series))))
DISPLAY "An entry in the database already has "
"that title. Please choose a different "
"title or remove the entry."
ELSE
PERFORM database-file-error
END-IF
END-WRITE
 
PERFORM close-database
(defun watch-latest ()
.
(format t "~{~a~%~}" (sort (get-latest *db*) #'compare-by-date)))
delete-entry.
PERFORM get-title-arg
OPEN I-O database-file
PERFORM read-title
 
DELETE database-file
(defun watch-all ()
(format t "~{~a~%~}" (sort (get-all *db*) #'compare-by-date)))
 
PERFORM close-database
(defun watch-new-series (&key name description tags)
.
(cdar (push (cons name (make-series :description description :tags tags)) *db*)))
display-specified-entry.
PERFORM get-title-arg
OPEN INPUT database-file
PERFORM read-title
 
PERFORM show-record
(defun get-or-add-series (name database)
(or (get-series name database)
(if (y-or-n-p "Add new series? [y/n]: ")
(watch-new-series
:name name
:description (prompt-read "Description" name)
:tags (parse-tags (prompt-read "Tags" "active")))
nil)))
 
PERFORM close-database
(defun watch-add ()
.
(let* ((series (loop thereis (get-or-add-series (prompt-read "Series") *db*)))
get-title-arg.
(episode (prompt-for-episode (car (series-episodes series)))))
DISPLAY 2 UPON ARGUMENT-NUMBER
(push episode (series-episodes series))))
ACCEPT data-title FROM ARGUMENT-VALUE
.
read-title.
START database-file KEY IS = data-title
INVALID KEY
IF key-not-found
DISPLAY "An entry with that title was not found."
PERFORM close-and-terminate
ELSE
PERFORM database-file-error
END-IF
END-START
 
READ database-file
(defun watch-series-names ()
.
(format T "~{~a~%~}"
close-and-terminate.
(sort (mapcar #'car *db*)
PERFORM (lambda (series1 series2) close-database
GOBACK
(compare-by-date (car (series-episodes (get-value series1 *db*)))
.
(car (series-episodes (get-value series2 *db*))))))))
show-latest.
OPEN INPUT database-file
 
PERFORM start-at-last-date
(defun watch-load (dbfile)
READ database-file
(setf *db* (load-db dbfile)))
PERFORM show-record
 
PERFORM close-database
.
show-database.
OPEN INPUT database-file
 
EVALUATE TRUE
(defun argv ()
WHEN print-by-title
*> Primary key is the title.
CONTINUE
WHEN print-by-tag
MOVE LOW-VALUES TO data-tag
START database-file KEY IS > data-tag
WHEN print-by-date
PERFORM start-at-last-date
SET read-backwards TO TRUE
END-EVALUATE
 
PERFORM FOREVER
*> The problem with statements instead of functions...
IF NOT read-backwards
READ database-file NEXT
AT END
EXIT PERFORM
END-READ
ELSE
READ database-file PREVIOUS
AT END
EXIT PERFORM
END-READ
END-IF
 
PERFORM show-record
DISPLAY SPACE
END-PERFORM
 
PERFORM close-database
.
start-at-last-date.
MOVE HIGH-VALUES TO date-added
START database-file KEY IS < date-added
.
close-database.
CLOSE database-file
.
show-record.
MOVE date-added TO edited-date
DISPLAY "Date added: " edited-date " Tag: " data-tag
DISPLAY "Title: " data-title
DISPLAY "Contents:"
DISPLAY " " FUNCTION TRIM(data-contents)
.
show-general-help.
DISPLAY "Help: Possible options are:"
DISPLAY " -a - Show all the entries (sorted by title)."
DISPLAY " -c - Create a new entry in the database. -c needs"
" further arguments in this format:"
DISPLAY ' "tag" "title" "content"'
DISPLAY " Max argument sizes (in characters): tag - 20, "
"title - 50, content - 200"
DISPLAY " The title must be unique and not be blank."
DISPLAY " -d - Show all the entries sorted by date added."
DISPLAY " -f - Finds and displays entry with the title "
"provided. The title should be specified as shown for "
"-c."
DISPLAY " -h - Show this help menu."
DISPLAY " -l - Show the latest entry."
DISPLAY " -r - Remove the entry with the title provided. "
"The title should be specified as shown for -c."
DISPLAY " -t - Show all the entries sorted by tag."
.</syntaxhighlight>
 
Sample session:
<pre>
$ ./database -c "Reminder" "Bob's Birthday" "Buy birthday present for Bob."
$ ./database -c "Wishlist" "Beethoven" "Beethoven's Ode to Joy"
$ ./database -c "Reminder" "Add to Simple Database" "Add brainf*** example for Simple Database on Rosetta Code."
...
$ ./database -f "Mozart"
An entry with that title was not found.
$ ./database -t
Date added: 2013/08/13 Tag: Reminder
Title: Bob's Birthday
Contents:
Buy birthday present for Bob.
Date added: 2013/08/13 Tag: Reminder
Title: Add to Simple Database
Contents:
Add brainf*** example for Simple Database on Rosetta Code.
Date added: 2013/08/13 Tag: Wishlist
Title: Beethoven
Contents:
Beethoven's Ode to Joy
 
$ ./database -r "Beethoven"
$ ./database -l
Date added: 2013/08/13 Tag: Reminder
Title: Add to Simple Database
Contents:
Add brainf*** example for Simple Database on Rosetta Code.
$
</pre>
 
=={{header|Common Lisp}}==
 
Tested with [[Common Lisp]]. ''(Save the code below as db.lisp)''
 
<syntaxhighlight lang="lisp">(defvar *db* nil)
 
(defvar *db-cat* (make-hash-table :test 'equal))
 
(defvar *db-file* "db.txt")
 
(defstruct item
"this is the unit of data stored/displayed in *db*"
(title " ")
(category "default")
(date (progn (get-universal-time))))
 
(defun set-category(new-item)
(setf (gethash (item-category new-item) *db-cat*) 't))
 
(defun find-item-in-db (&optional category)
(if (null category)
(car *db*)
(find category *db* :key #'item-category :test #'string=)))
 
(defun scan-category ()
"scan categories from an existing database -- after reading it from disk"
(dolist (itm *db*) (set-category itm)))
 
(defun pr-univ-time (utime)
(multiple-value-bind
(second minute hour date month year day-of-week dst-p tz)
(decode-universal-time utime)
(declare (ignore day-of-week dst-p tz))
(format nil "~4,'0d-~2,'0d-~2,'0d ~2,'0d:~2,'0d:~2,'0d" year month date hour minute second)))
 
(defun pr (&optional (item (find-item-in-db)) (stream t))
"print an item"
(when item
(format stream "~a: (~a) (~a)~%"
(item-title item)
(item-category item)
(pr-univ-time (item-date item)))))
 
(defun pr-per-category ()
"print the latest item from each category"
(loop for k being the hash-keys in *db-cat*
do (pr (find-item-in-db k))))
 
(defun pr-all ()
"print all the items, *db* is sorted by time."
(dolist (itm *db*) (pr itm)))
 
(defun pr-all-categories (&optional (stream t))
(loop for k being the hash-keys in *db-cat*
do (format stream "(~a) " k)))
(defun insert-item (item)
"insert item into database in a time sorted list. okay for a small list, as per spec."
(let ((first-item (car *db*)) (new-itm item))
(set-category new-itm)
(push new-itm *db*)
(when (and first-item (>= (item-date new-itm) (item-date first-item)))
(setf *db* (sort *db* #'> :key #'item-date)))
*db*))
 
(defun read-db-from-file (&optional (file *db-file*))
(with-open-file (in file :if-does-not-exist nil)
(when in
(with-standard-io-syntax (setf *db* (read in)))
(scan-category))))
 
(defun save-db-to-file (&optional (file *db-file*))
(with-open-file (out file :direction :output :if-exists :supersede)
(with-standard-io-syntax
(print *db* out))))
 
(defun del-db ()
(setf *db* nil)
(save-db-to-file))
 
(defun del-item (itm)
(read-db-from-file)
(setf *db* (remove itm *db* :key #'item-title :test #'string=))
(save-db-to-file))
 
(defun add-item-to-db (args)
(read-db-from-file)
(insert-item (make-item :title (first args) :category (second args)))
(save-db-to-file))
 
(defun help-menu ()
(format t "clisp db.lisp ~{~15T~a~^~% ~}"
'("delete <item-name> ------------------- delete an item"
"delete-all --------------------------- delete the database"
"insert <item-name> <item-category> --- insert an item with its category"
"show --------------------------------- shows the latest inserted item"
"show-categories ---------------------- show all categories"
"show-all ----------------------------- show all items"
"show-per-category -------------------- show the latest item per category")))
 
(defun db-cmd-run (args)
(cond ((and (> (length args) 1) (equal (first args) "delete"))
(del-item (second args)))
((equal (first args) "delete-all") (del-db))
((and (> (length args) 2) (equal (first args) "insert"))
(add-item-to-db (rest args)))
((equal (first args) "show") (read-db-from-file) (pr))
((equal (first args) "show-categories") (read-db-from-file) (pr-all-categories))
((equal (first args) "show-all") (read-db-from-file) (pr-all))
((equal (first args) "show-per-category") (read-db-from-file) (pr-per-category))
(t (help-menu))))
 
;; modified https://rosettacode.org/wiki/Command-line_arguments#Common_Lisp
(defun db-argv ()
(or
#+clisp (ext:argv)*args*
#+sbcl (cdr sb-ext:*posix-argv*)
#+clozureallegro (ccl:cdr (sys:command-line-arguments))
#+gcllispworks si(cdr sys:*commandline-arguments-argslist*)
nil))
#+ecl (loop for i from 0 below (si:argc) collect (si:argv i))
 
#+cmu extensions:*command-line-strings*
(db-cmd-run (db-argv))</syntaxhighlight>
#+allegro (sys:command-line-arguments)
 
#+lispworks sys:*line-arguments-list*
 
nil))
Help menu:
$ clisp db.lisp
clisp db.lisp delete <item-name> ------------------- delete an item
delete-all --------------------------- delete the database
insert <item-name> <item-category> --- insert an item with its category
show --------------------------------- shows the latest inserted item
show-categories ---------------------- show all categories
show-all ----------------------------- show all items
show-per-category -------------------- show the latest item per category
 
Here are a few steps to add a few titles, and their categories:
$ clisp db.lisp insert "title-vinyl-1" "vinyl"
$ clisp db.lisp insert "title-cd-1" "cd"
$ clisp db.lisp insert "title-dvd-1" "dvd"
$ clisp db.lisp insert "title-tape-1" "tape"
$ clisp db.lisp insert "title-tape-2" "tape"
 
Here is the very latest entry in the db:
$ clisp db.lisp show
title-tape-2: (tape) (2017-04-04 20:19:06)
 
Here is a (sorted time wise) list of all the entries:
$ clisp db.lisp show-all
title-tape-2: (tape) (2017-04-04 20:19:06)
title-tape-1: (tape) (2017-04-04 20:19:00)
title-dvd-1: (dvd) (2017-04-04 20:18:55)
title-cd-1: (cd) (2017-04-04 20:18:48)
title-vinyl-1: (vinyl) (2017-04-04 20:18:41)
 
Here is the latest entry for each category:
$ clisp db.lisp show-per-category
title-vinyl-1: (vinyl) (2017-04-04 20:18:41)
title-cd-1: (cd) (2017-04-04 20:18:48)
title-dvd-1: (dvd) (2017-04-04 20:18:55)
title-tape-2: (tape) (2017-04-04 20:19:06)
 
Here is the list of all categories:
$ clisp db.lisp show-categories
(vinyl) (cd) (dvd) (tape)
 
To delete an entry:
$ clisp db.lisp delete "title-tape-2"
 
To delete all entries:
$ clisp db.lisp delete-all
 
=={{header|D}}==
<syntaxhighlight lang="d">import std.stdio, std.algorithm, std.string, std.conv, std.array,
std.file, std.csv, std.datetime;
 
private {
immutable filename = "simdb.csv";
 
struct Item {
string name, date, category;
}
 
void addItem(in string[] item) {
if (item.length < 3)
return printUsage();
auto db = load();
const date = (cast(DateTime)Clock.currTime).toISOExtString;
const cat = (item.length == 4) ? item[3] : "none";
db ~= Item(item[2], date, cat);
store(db);
}
 
void printLatest(in string[] a) {
auto db = load();
if (db.empty)
return writeln("No entries in database.");
db.sort!q{ a.date > b.date };
if (a.length == 3) {
foreach (item; db)
if (item.category == a[2])
writefln("%s, %s, %s", item.tupleof);
} else {
writefln("%s, %s, %s", db[0].tupleof);
}
}
 
void printAll() {
auto db = load();
if (db.empty)
return writeln("No entries in database.");
db.sort!q{ a.date < b.date };
foreach (item; db)
writefln("%s, %s, %s", item.tupleof);
}
 
Item[] load() {
Item[] db;
if (filename.exists && filename.isFile) {
try {
const text = filename.readText;
if (!text.empty)
db = csvReader!Item(text).array;
} catch (CSVException e) {
writeln(e.msg);
}
}
return db;
}
 
void store(in Item[] db) {
auto f = File(filename, "w+");
foreach (item; db)
f.writefln("%s,%s,%s", item.tupleof);
}
 
void printUsage() {
writeln(
`Usage:
simdb cmd [categoryName]
 
add add item, followed by optional category
latest print last added item(s), followed by optional category
all print all
 
For instance: add "some item name" "some category name"`);
}
}
 
void main(in string[] args) {
if (args.length < 2 || args.length > 4)
return printUsage();
 
switch (args[1].toLower) {
case "add": addItem(args); break;
case "latest": printLatest(args); break;
case "all": printAll(); break;
default: printUsage(); break;
}
}</syntaxhighlight>
{{out}}
<pre>C:\>simdb add item1 cat1
 
C:\>simdb add item2 cat2
 
C:\>simdb add item3 cat3
 
C:\>simdb add item4
 
C:\>simdb add item5
 
C:\>simdb add item6 cat4
 
C:\>simdb add item7 cat4
 
C:\>simdb latest
item7, 2014-06-04T16:02:01, cat4
 
C:\>simdb latest cat4
item7, 2014-06-04T16:02:01, cat4
item6, 2014-06-04T16:01:55, cat4
 
C:\>simdb all
item1, 2014-06-04T16:01:26, cat1
item2, 2014-06-04T16:01:34, cat2
item3, 2014-06-04T16:01:41, cat3
item4, 2014-06-04T16:01:46, none
item5, 2014-06-04T16:01:49, none
item6, 2014-06-04T16:01:55, cat4
item7, 2014-06-04T16:02:01, cat4
 
C:\>simdb add
Usage:
simdb cmd [categoryname]
 
add add item, followed by optional category
latest print last added item(s), followed by optional category
all print all
 
For instance: add "some item name" "some category name"</pre>
File:
<pre>item1,2014-06-04T16:01:26,cat1
item2,2014-06-04T16:01:34,cat2
item3,2014-06-04T16:01:41,cat3
item4,2014-06-04T16:01:46,none
item5,2014-06-04T16:01:49,none
item6,2014-06-04T16:01:55,cat4
item7,2014-06-04T16:02:01,cat4</pre>
 
=={{header|Emacs Lisp}}==
<syntaxhighlight lang="lisp">
(defun dbe-next-id ()
(unless (boundp '**dbe-current-id**) (setq **dbe-current-id** 1))
(let ((id **dbe-current-id**))
(cl-incf **dbe-current-id**)
id ) )
 
(defun dbe-rows (fn-handle-row &rest params)
(let ((has-more 't) current-line linum1 linum2
(fn-continue (plist-get params :continue)))
(save-window-excursion
(switch-to-buffer "**content**")
(beginning-of-buffer)
(if fn-continue (setq has-more (funcall fn-continue)))
(while has-more
(setq current-line
(buffer-substring (line-beginning-position)
(line-end-position)))
(unless (string= current-line "")
(funcall fn-handle-row (read current-line)))
(if fn-continue (setq has-more (funcall fn-continue)))
(setq linum1 (line-number-at-pos (point)))
(forward-line)
(setq linum2 (line-number-at-pos (point)))
(if (= linum1 linum2) (setq has-more nil))
)
)
)
)
(defun dbe-insert (row)
(interactive "xPlease enter the row data in plist format: ")
(save-window-excursion
(switch-to-buffer "**content**")
(end-of-buffer)
(let (row-data)
(setq row-data (append (list 'id (dbe-next-id)) (ensure-list row)))
(insert (format "%s\n" row-data))
(message ">> Row added: %s" row-data) ) ) )
 
(defun dbe-find-by-id (row-id)
(interactive "nPlease enter row id: ")
(let (row-found)
(dbe-rows (lambda (row)
(when (equal (plist-get row 'id) row-id)
(setq row-found row)) )
:continue (lambda () (null row-found)))
(message ">> Row found: %s" row-found)
)
)
</syntaxhighlight>
 
{{out}}
 
<pre>
M-x dbe-insert
Please enter the row data in plist format: (name "book1" author "author1")
>> Row added: (id 1 name book1 author author1)
 
M-x dbe-insert
Please enter the row data in plist format: (name "book2" author "author2")
>> Row added: (id 2 name book2 author author2)
 
M-x dbe-find-by-id
Please enter row id: 2
>> Row found: (id 2 name book2 author author2)
</pre>
 
=={{header|Erlang}}==
<syntaxhighlight lang="erlang">
#! /usr/bin/env escript
 
-compile({no_auto_import,[date/0]}).
 
main( ["add", Tag | Descriptions] ) -> add( date(), Tag, Descriptions );
main( ["add_date", Date, Tag | Descriptions] ) -> add( date_internal(string:tokens(Date, "-")), Tag, Descriptions );
main( ["print_latest"] ) -> print_latest( contents() );
main( ["print_latest_for_each"] ) -> print_latest_for_each( contents() );
main( ["print_all_date", Date] ) -> print_all_date( date_internal(string:tokens(Date, "-")), contents() );
main( _Error ) -> usage().
 
 
 
add( Date, Tag, Descriptions ) ->
Contents = contents(),
file:write_file( file(), io_lib:format("simple_database_v1.~n~p.~n", [[{Date, Tag, Descriptions} | Contents]]) ).
 
date() ->
{{Date, _Time}} = calendar:local_time(),
Date.
 
date_external( {Year, Month, Day} ) -> string:join( [erlang:integer_to_list(Year), erlang:integer_to_list(Month), erlang:integer_to_list(Day)], "-" );
date_external( _Error ) -> usage().
 
date_internal( [Year, Month, Day] ) -> {erlang:list_to_integer(Year), erlang:list_to_integer(Month), erlang:list_to_integer(Day)};
date_internal( _Error ) -> usage().
 
file() -> "simple_database_contents".
 
contents() -> contents( file:consult(file()) ).
 
contents( {ok, [simple_database_v1, Contents]} ) -> Contents;
contents( {error, Error} ) when is_atom(Error) -> [];
contents( {error, _Error} ) ->
io:fwrite( "Error: ~p corrupt. Starting from scratch~n", [file()] ),
[].
 
print_all_date( _Date, [] ) -> ok;
print_all_date( Date, Contents ) -> [print_latest([{D, Tag, Descriptions}]) || {D, Tag, Descriptions} <- Contents, D =:= Date].
 
print_latest( [] ) -> ok;
print_latest( [{Date, Tag, Descriptions} | _T] ) -> io:fwrite( "~s~n", [string:join( [date_external(Date), Tag | Descriptions], " ")] ).
 
print_latest_for_each( [] ) -> ok;
print_latest_for_each( Contents ) ->
Tags = lists:usort( [Tag || {_Date, Tag, _Descriptions} <- Contents] ),
[print_latest([lists:keyfind(X, 2, Contents)]) || X <- Tags].
 
usage() ->
io:fwrite( "Usage: ~p [add | add_date <date>] tag description ...~n", [escript:script_name()] ),
io:fwrite( "Or: ~p [print_latest | print_latest_for_each | print_all_date <date>]~n", [escript:script_name()] ),
io:fwrite( "Date format is YYYY-MM-DD~n" ),
io:fwrite( "Data stored in ~p~n", [file()] ),
init:stop().
</syntaxhighlight>
Command line session started with these file contents as database:
<pre>
simple_database_v1.
[{{2013,9,16},"comic",["hobbe"]},
{{2013,9,16},"comic",["gustaf"]}].
</pre>
Command line session:
<pre>
./simple_database add num 1 2 3
./simple_database add_date 1991-01-01 num 999 888
./simple_database print_latest
1991-1-1 num 999 888
./simple_database print_latest_for_each
2013-9-16 comic hobbe
1991-1-1 num 999 888
./simple_database print_all_date 2013-09-16
2013-9-16 num 1 2 3
2013-9-16 comic hobbe
2013-9-16 comic gustaf
</pre>
 
=={{header|Forth}}==
Simple in-memory database. Load/dump database from/to a file.
 
{{works with|GNU Forth|Gforth|0.7}}
Example file 'test.sdb':
<pre>
+: betty 1974.03.03;coworker;reading;
 
+: geea 1980.01.01;friend;sketch writer;
 
+: tom 1991.03.07;family member;reading;
 
+: alice 1987.09.01;coworker;classical music;
 
+: gammaQ3.14 3045.09.09;friend;watch movies, star walking;
</pre>
 
Example usage:
<pre>
$ gforth sdb.fs
 
help
 
[ -erased help message- ]
 
load test.sdb ok
 
.keys
 
gammaQ3.14 alice tom geea betty ok
 
betty .record betty 1974.03.03;coworker;reading; ok
 
newline geea .record
 
geea 1980.01.01;friend;sketch writer; ok
 
+: theea 1979.04.05;coworker;astronomy; ok
 
newline .bydate
 
gammaQ3.14 3045.09.09;friend;watch movies, star walking;
 
tom 1991.03.07;family member;reading;
 
alice 1987.09.01;coworker;classical music;
 
geea 1980.01.01;friend;sketch writer;
 
theea 1979.04.05;coworker;astronomy;
 
betty 1974.03.03;coworker;reading;
 
dump t2.sdb ok
 
bye
 
$
 
$ cat t2.sdb
 
+: betty 1974.03.03;coworker;reading;
 
+: geea 1980.01.01;friend;sketch writer;
 
+: tom 1991.03.07;family member;reading;
 
+: alice 1987.09.01;coworker;classical music;
 
+: gammaQ3.14 3045.09.09;friend;watch movies, star walking;
 
+: theea 1979.04.05;coworker;astronomy;
 
$
</pre>
 
Code:
<syntaxhighlight lang="forth">\ sdb.fs Simple database. Gforth 0.7.0 specific
' noop is bootmessage
 
wordlist constant USER: \ USER functions
wordlist constant SDB \ DB keys
wordlist constant FIELDS \ DB fields
 
: -SDB?EXIT ( -- ; Continue if `SDB' non-empty )
SDB cell+ @ 0= IF rdrop exit THEN ;
 
\ MACROS
: |comp| ( MACRO: | code to be compiled | )
char parse evaluate ; immediate
: LIST ( node -- ) ]] BEGIN @ dup WHILE >R [[ ; immediate
: LOOP-LIST ( -- ) ]] R> REPEAT drop [[ ; immediate
: UNLIST ( -- ) POSTPONE rdrop ; immediate
 
\ Helper words
: .; [char] ; emit ;
: !+ dup cell+ -rot ! ;
: ($+) ( cas us cad ud -- cad us+ud ; append source string to destination )
swap >R 2dup + R> swap >R tuck + swap >R swap move R> R> ;
 
\ --- Working Record Fields
current @ FIELDS current !
2variable person
2variable birthday
2variable relationship
2variable hobby
current ! FIELDS >order
 
\ --- Ring list
: new-node ( -- node ; root of circular list )
here dup , ;
: do-link ( node new-node -- ; do link after current node )
over @ over ! swap ! ;
: empty-ring? ( node -- f ) dup @ = ;
 
: RING ( node -- ) ]] dup BEGIN @ 2dup <> WHILE 2>R [[ ; immediate
: LOOP-RING ( -- ) ]] 2R> REPEAT 2drop [[ ; immediate
: UNRING ( -- ) postpone 2RDROP ; immediate
 
:noname
s" " person 2! s" 9999.01.01" birthday 2! s" " relationship 2! s" " hobby 2! ;
new-node swap , CONSTANT OLD
 
\ --- Insertion into ring
: node>xt ( node -- xt ) cell+ @ ;
: bday@ ( node -- ca u ) node>xt execute birthday 2@ ;
: datecmp ( node node -- -1|0|1 ) bday@ rot bday@ compare ;
 
: search-by-date ( new-node node -- node' ; Linear search by birth date )
dup
RING ( new-node node )
over I datecmp 0<
IF nip UNRING exit
ELSE drop I THEN
LOOP-RING nip ;
 
: insert-ordered ( new-node -- )
OLD dup empty-ring? 0=
IF over swap search-by-date THEN swap do-link ;
 
\ --- Field compiling
: fld: [char] ; parse postpone sliteral ; immediate
 
: _sdb-walk ( MACRO: | xt[--] -- | )
]] -SDB?EXIT here dup SDB cell+
LIST I name>int swap !+ LOOP-LIST [[ 1 cells ]] literal -
DO I @ |comp| [[ -1 cells ]] literal +LOOP [[ ; immediate
 
2variable category
: msg_nocategory ( -- )
." No such category!" cr ;
 
\ --- USER definitions
user: >order current @ USER: current !
: bye bye ;
: .s .s ;
: newline cr ;
: godb SDB >order ;
: .keys SDB wordlist-words ;
: .person person 2@ type ;
: .birthday birthday 2@ type ;
: .relationship relationship 2@ type ;
: .hobby hobby 2@ type ;
: .record .person 1 spaces .birthday .; .relationship .; .hobby .; ;
 
: .last SDB cell+ @ dup
IF name>int execute .record ELSE drop THEN ;
 
: .lastbycategory ( "field-name" -- )
here 0 category 2! parse-name FIELDS search-wordlist
IF sdb cell+
LIST ( xt )
I name>int execute dup execute 2@ category 2@ 2swap search nip nip 0=
IF .record cr dup execute 2@ category 2@ ($+) category 2! THEN
LOOP-LIST drop
ELSE ['] msg_nocategory stderr OUTFILE-EXECUTE THEN ;
 
: .bydate ( -- )
OLD RING I node>xt execute .record cr LOOP-RING ;
 
: .sdb _sdb-walk | execute .record cr | ;
: sdb-dump _sdb-walk | execute ." +: " .record cr | ;
 
: dump ( "db-file" -- )
parse-name w/o
CREATE-FILE throw dup
['] sdb-dump swap OUTFILE-EXECUTE
CLOSE-FILE throw ;
 
: load ( "db-file" -- ) include ;
 
: +: ( "person birth-day;relationship;hobby; -- )
(defun main (argv)
new-node dup cell+ >R 0 , \ post `xt'
(let ((dbfile (make-pathname :name "lwatch" :type nil :defaults *load-pathname*)))
current @ SDB current ! \ compile into `sdb' wordlist
(watch-load dbfile)
: latestxt dup R> ! \ fix-up `xt'
(cond ((equal (cadr argv) "add") (watch-add) (watch-save dbfile))
]] literal >name name>string person 2! fld: birthday 2! fld: relationship 2! fld: hobby 2! ; [[
((equal (cadr argv) "latest") (watch-latest))
current !
((null (cadr argv)) (watch-latest))
insert-ordered ;
((equal (cadr argv) "series") (watch-series-names))
((equal (cadr argv) "all") (watch-all))
(T (watch-series (format nil "~{~a~^ ~}" (cdr argv)))))))
 
: HELP cr
(main (argv))</lang>
cr ." KEYWORDS: " USER: wordlist-words cr ." ---"
cr ." Prefix `.' means print"
cr ." To add a record, type: +: name yyyy.mm.dd;relationship;hobby;"
cr cr ;
current !
SEAL godb</syntaxhighlight>
 
=={{header|Go}}==
<langsyntaxhighlight lang="go">package main
 
import (
Line 785 ⟶ 2,299:
fmt.Println(err)
}
}</langsyntaxhighlight>
 
=={{header|Haskell}}==
 
The database is a list of type Item stored in a StateT monad transformer that allows for IO actions to be perfomed with it (StateT [Item] IO a). All IO actions occurring inside the StateT monad (handling command line arguments and printing items) must be lifted.
The database is written to disk using "show" and read back using "read". Therefore, Item is declared as an instance of both Show and Read classes. An item in the database file looks like the following:
Item {description = "La traviata", category = ["Classical"], date = Date 2012 10 19, optional = ["Giuseppe Verdi","1853"]}
 
<syntaxhighlight lang="haskell">import Control.Monad.State
import Data.List (sortBy, nub)
import System.Environment (getArgs, getProgName)
import System.Directory (doesFileExist)
import System.IO (openFile, hGetContents, hClose, IOMode(..),
Handle, hPutStrLn)
 
-- for storing dates
data Date = Date Integer Int Int deriving (Show, Read, Eq, Ord)
 
-- for storing database items
data Item = Item {description :: String
,category :: [String]
,date :: Date
,optional :: [String]}
deriving (Show, Read)
 
-- a state monad transformer which wraps IO actions.
-- the database (state) is passed implicitly between functions.
type ItemList a = StateT [Item] IO a
 
-- add an item to the database
addItem :: Item -> ItemList ()
addItem i = modify (++ [i])
 
-- get the newest of a list of items
latest :: [Item] -> [Item]
latest [] = []
latest [x]= [x]
latest xs = take 1 $ sortBy newer xs
 
-- compare two items to see which one is newer
newer :: Item -> Item -> Ordering
newer a b = compare (date b) (date a)
 
-- list all different categories (no duplicates)
categories :: ItemList [String]
categories = liftM (nub . concatMap category) get
 
-- list only the items with the given category tag
filterByCategory :: String -> ItemList [Item]
filterByCategory c = liftM (filter (\i -> c `elem` category i)) get
 
-- get the newest of all items
lastOfAll :: ItemList [Item]
lastOfAll = liftM latest get
-- get the newest item in each category
latestByCategory :: ItemList [Item]
latestByCategory = do
cats <- categories
filt <- mapM filterByCategory cats
return $ concatMap latest filt
 
-- sort all items chronologically, newest first
sortByDate :: ItemList [Item]
sortByDate = liftM (sortBy newer) get
 
toScreen :: Item -> IO ()
toScreen (Item desc cats (Date y m d) opt) = putStrLn $
"Description:\t" ++ desc ++ "\nCategories:\t" ++ show cats ++
"\nDate:\t\t" ++ show y ++ "-" ++ show m ++ "-" ++ show d ++
"\nOther info:\t" ++ show opt
 
-- command line argument handling
-- if the user called the program with the option "add", the
-- new item is returned to main so that it can be saved to disk.
-- the argument "opt" is a list.
arguments :: ItemList [Item]
arguments = do
args <- liftIO getArgs
case args of
("add":desc:cat:year:month:day:opt) -> do
let newItem = parseItem args
addItem newItem
return [newItem]
("latest":[]) -> do
item <- lastOfAll
lift $ mapM_ toScreen item
return []
("category":[]) -> do
items <- latestByCategory
lift $ mapM_ toScreen items
return []
("all":[]) -> do
sorted <- sortByDate
lift $ mapM_ toScreen sorted
return []
_ -> do
lift usage
return []
 
parseItem :: [String] -> Item
parseItem (_:desc:cat:year:month:day:opt) =
Item {description = desc, category = words cat,
date = Date (read year) (read month) (read day),
optional = opt}
usage :: IO ()
usage = do
progName <- getProgName
putStrLn $ "Usage: " ++ progName ++ " add|all|category|latest \
\OPTIONS\n\nadd \"description\" \"category1 category2\"... \
\year month day [\"note1\" \"note2\"...]\n\tAdds a new record \
\to the database.\n\nall\n\tPrints all items in chronological \
\order.\n\ncategory\n\tPrints the latest item for each category.\
\\n\nlatest\n\tPrints the latest item."
 
-- the program creates, reads and writes to a file in the current directory
main :: IO ()
main = do
progName <- getProgName
let fileName = progName ++ ".db"
e <- doesFileExist fileName
if e
then do
hr <- openFile fileName ReadMode
f <- hGetContents hr
v <- evalStateT arguments (map read $ lines f)
hClose hr -- must be called after working with contents!
hw <- openFile fileName AppendMode
mapM_ (hPutStrLn hw . show) v
hClose hw
else do
v <- evalStateT arguments []
hw <- openFile fileName WriteMode
mapM_ (hPutStrLn hw . show) v
hClose hw
</syntaxhighlight>
 
=={{header|J}}==
 
J comes with a sql database, jdb. Jdb's columns are memory mapped files with header information. These won't meet the human readable data file requirement. Hence, this program:
 
<langsyntaxhighlight lang="j">HELP=: 0 :0
Commands:
 
Line 898 ⟶ 2,549:
 
exit 0
</syntaxhighlight>
</lang>
Assume the j code is stored in file s . These bash commands, stored in file input , create a database using add .
<langsyntaxhighlight lang="sh">D='jconsole s dataflow'
$D add name expression algebraic rank valence example explanation
Line 913 ⟶ 2,564:
$D add atop 'x f@g y' 'f(g(x,y))' 'rank of g' dyad '>@{.' '(lisp) open the car'
$D add 'many more!'
</syntaxhighlight>
</lang>
Now we look up data from the bash command line.
<syntaxhighlight lang="sh">
<lang sh>
$ . input # source the input
$ echo $D
Line 991 ⟶ 2,642:
'2012-02-08:23:45:06.515';'atop';'x f@g y';'f(g(x,y))';'rank of g';'dyad';'>@{.';'(lisp) open the car'
'2012-02-08:23:45:06.539';'many more!'
$ </langsyntaxhighlight>
 
=={{header|Java}}==
{{trans|D}}
{{works with|Java|7}}
<syntaxhighlight lang="java">import java.io.*;
import java.text.*;
import java.util.*;
 
public class SimpleDatabase {
 
final static String filename = "simdb.csv";
 
public static void main(String[] args) {
if (args.length < 1 || args.length > 3) {
printUsage();
return;
}
 
switch (args[0].toLowerCase()) {
case "add":
addItem(args);
break;
case "latest":
printLatest(args);
break;
case "all":
printAll();
break;
default:
printUsage();
break;
}
}
 
private static class Item implements Comparable<Item>{
final String name;
final String date;
final String category;
 
Item(String n, String d, String c) {
name = n;
date = d;
category = c;
}
 
@Override
public int compareTo(Item item){
return date.compareTo(item.date);
}
 
@Override
public String toString() {
return String.format("%s,%s,%s%n", name, date, category);
}
}
 
private static void addItem(String[] input) {
if (input.length < 2) {
printUsage();
return;
}
List<Item> db = load();
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
String date = sdf.format(new Date());
String cat = (input.length == 3) ? input[2] : "none";
db.add(new Item(input[1], date, cat));
store(db);
}
 
private static void printLatest(String[] a) {
List<Item> db = load();
if (db.isEmpty()) {
System.out.println("No entries in database.");
return;
}
Collections.sort(db);
if (a.length == 2) {
for (Item item : db)
if (item.category.equals(a[1]))
System.out.println(item);
} else {
System.out.println(db.get(0));
}
}
 
private static void printAll() {
List<Item> db = load();
if (db.isEmpty()) {
System.out.println("No entries in database.");
return;
}
Collections.sort(db);
for (Item item : db)
System.out.println(item);
}
 
private static List<Item> load() {
List<Item> db = new ArrayList<>();
try (Scanner sc = new Scanner(new File(filename))) {
while (sc.hasNext()) {
String[] item = sc.nextLine().split(",");
db.add(new Item(item[0], item[1], item[2]));
}
} catch (IOException e) {
System.out.println(e);
}
return db;
}
 
private static void store(List<Item> db) {
try (FileWriter fw = new FileWriter(filename)) {
for (Item item : db)
fw.write(item.toString());
} catch (IOException e) {
System.out.println(e);
}
}
 
private static void printUsage() {
System.out.println("Usage:");
System.out.println(" simdb cmd [categoryName]");
System.out.println(" add add item, followed by optional category");
System.out.println(" latest print last added item(s), followed by "
+ "optional category");
System.out.println(" all print all");
System.out.println(" For instance: add \"some item name\" "
+ "\"some category name\"");
}
}</syntaxhighlight>
 
Output:
 
<pre>
C:\temp>java -jar SimpleDatabase.jar add item1
 
C:\temp>java -jar SimpleDatabase.jar add item2
 
C:\temp>java -jar SimpleDatabase.jar add item3 cat3
 
C:\temp>java -jar SimpleDatabase.jar add item4 cat3
 
C:\temp>java -jar SimpleDatabase.jar add item5 cat3
 
C:\temp>java -jar SimpleDatabase.jar latest
item1,2014-06-03 19:30:05,none
 
C:\temp>java -jar SimpleDatabase.jar latest cat3
item3,2014-06-03 19:30:14,cat3
 
item4,2014-06-03 19:30:20,cat3
 
item5,2014-06-03 19:30:23,cat3
 
C:\temp>java -jar SimpleDatabase.jar all
item1,2014-06-03 19:30:05,none
 
item2,2014-06-03 19:30:08,none
 
item3,2014-06-03 19:30:14,cat3
 
item4,2014-06-03 19:30:20,cat3
 
item5,2014-06-03 19:30:23,cat3</pre>
 
=={{header|Julia}}==
Command line CSV based simple database. The file used contained:<pre>
Name,Birthdate,State,Relation,Email
Sally Whittaker,1988-12-05,Illinois,friend,sally@mail.com
Belinda Jameson,1994-02-17,California,family,beljames@example.com
Jeff Bragg,2018-10-10,Texas,family,jb@texas.edu
Sandy Allen,2002-03-09,Colorado,friend,sandya@mail.com
Fred Kobo,1967-10-10,Colorado,friend,fkobo@example.net</pre>
<syntaxhighlight lang="julia">using CSV, DataFrames, ArgParse, Dates
 
setting = ArgParseSettings()
@add_arg_table setting begin
"--add"
help = "add an entry, within double quotes, comma separated as \"name,birthdate,state,relation,email\" with birthdate as yyyy-mm-dd"
"--latest"
action = :store_true
nargs = 0
help = "print latest (last) entry"
"--latestfriend"
action = :store_true
nargs = 0
help = "print last friend listed"
"--latestfamily"
action = :store_true
nargs = 0
help = "print last family member listed"
"--listbyage"
action = :store_true
nargs = 0
help = "print all ages and entries in birth order"
end
 
const filename = "example.csv"
const df = CSV.File(filename, dateformat="yyyy-mm-dd") |> DataFrame
const commands = parse_args(setting)
if length(ARGS) == 0
ArgParse.show_help(setting)
end
const changeflag = [false]
 
for (k, v) in commands
if k == "add" && v != nothing
newrow = Vector{Any}(split(v, r","))
if length(newrow) == 5 && tryparse(DateTime, newrow[2]) != nothing
newrow[2] = DateTime(newrow[2])
push!(df, newrow)
changeflag[1] = true
println("Added entry $newrow.")
end
elseif k == "latest" && v
println("The latest entry is $(df[end, :])")
elseif k == "latestfriend" && v
println(df[df.Relation .== "friend", :][end, :])
elseif k == "latestfamily" && v
println(df[df.Relation .== "family", :][end, :])
elseif k == "listbyage" && v
dobcol = df[:Birthdate]
age = map(x -> round((now() - DateTime(x)).value /(1000*3600*24*365.25), digits=1), dobcol)
df2 = deepcopy(df)
df2 = insert!(df, 1, age, :Age)
println(sort(df2, (:Age)))
end
end
 
if changeflag[1]
CSV.write(filename, df)
println("Changes written to file $filename.")
end
</syntaxhighlight>
 
=={{header|Kotlin}}==
{{trans|Java}}
... though not quite the same.
<syntaxhighlight lang="scala">// version 1.2.31
 
import java.text.SimpleDateFormat
import java.util.Date
import java.io.File
import java.io.IOException
 
val file = File("simdb.csv")
 
class Item(
val name: String,
val date: String,
val category: String
) : Comparable<Item> {
 
override fun compareTo(other: Item) = date.compareTo(other.date)
 
override fun toString() = "$name, $date, $category"
}
 
fun addItem(input: Array<String>) {
if (input.size < 2) {
printUsage()
return
}
val sdf = SimpleDateFormat("yyyy-MM-dd HH:mm:ss")
val date = sdf.format(Date())
val cat = if (input.size == 3) input[2] else "none"
store(Item(input[1], date, cat))
}
 
fun printLatest(a: Array<String>) {
val db = load()
if (db.isEmpty()) {
println("No entries in database.")
return
}
// no need to sort db as items are added chronologically
if (a.size == 2) {
var found = false
for (item in db.reversed()) {
if (item.category == a[1]) {
println(item)
found = true
break
}
}
if (!found) println("There are no items for category '${a[1]}'")
}
else println(db[db.lastIndex])
}
 
fun printAll() {
val db = load()
if (db.isEmpty()) {
println("No entries in database.")
return
}
// no need to sort db as items are added chronologically
for (item in db) println(item)
}
 
fun load(): MutableList<Item> {
val db = mutableListOf<Item>()
try {
file.forEachLine { line ->
val item = line.split(", ")
db.add(Item(item[0], item[1], item[2]))
}
}
catch (e: IOException) {
println(e)
System.exit(1)
}
return db
}
 
fun store(item: Item) {
try {
file.appendText("$item\n")
}
catch (e: IOException) {
println(e)
}
}
 
fun printUsage() {
println("""
|Usage:
| simdb cmd [categoryName]
| add add item, followed by optional category
| latest print last added item(s), followed by optional category
| all print all
| For instance: add "some item name" "some category name"
""".trimMargin())
}
 
fun main(args: Array<String>) {
if (args.size !in 1..3) {
printUsage()
return
}
file.createNewFile() // create file if it doesn't already exist
when (args[0].toLowerCase()) {
"add" -> addItem(args)
"latest" -> printLatest(args)
"all" -> printAll()
else -> printUsage()
}
}</syntaxhighlight>
 
{{out}}
Sample session.
<pre>
$ java -jar SimpleDatabase.jar add item1
$ java -jar SimpleDatabase.jar add item2
$ java -jar SimpleDatabase.jar add item3 cat3
$ java -jar SimpleDatabase.jar add item4 cat3
$ java -jar SimpleDatabase.jar add item5 cat3
$ java -jar SimpleDatabase.jar latest
item5, 2018-03-23 16:49:46, cat3
$ java -jar SimpleDatabase.jar latest none
item2, 2018-03-23 16:49:28, none
$ java -jar SimpleDatabase.jar latest cat4
There are no items for category 'cat4'
$ java -jar SimpleDatabase.jar all
item1, 2018-03-23 16:49:25, none
item2, 2018-03-23 16:49:28, none
item3, 2018-03-23 16:49:34, cat3
item4, 2018-03-23 16:49:40, cat3
item5, 2018-03-23 16:49:46, cat3
</pre>
 
=={{header|M2000 Interpreter}}==
Write the code on a UTF-8 text file as tool.gsb
 
Assign gsb files to open with M2000.exe (the M2000 environment)
 
Open the folder where exist tool.gsb in a cmd window
 
then follow the > lines in the out session
 
The format of file is xml, Utf8 with a BOM.
 
The M2000 environment not used here, all the output redirect to console. (Although the environment is a Window program, we can attach the console).
 
 
<syntaxhighlight lang="m2000 interpreter">
MODULE GLOBAL interpret {
global filename$="base1.xml"
module latest {
PrintConsoleLn("The latest entry is:")
if exist(filename$) else exit
declare xml xmlData
with xml, "xml" as doc$, "beautify" as beautify
doc$=string$(eval$(buffer(filename$)) as UTF8dec)
with xml, "lastchild" set child
with child,"attr" as attr$()
PrintConsoleLn(attr$("name")+","+@tag$()+","+attr$("date"))
declare xml nothing
}
module latestForEachTag {
PrintConsoleLn("latest entry for each tag:")
if exist(filename$) else exit
declare xml xmlData
with xml, "xml" as doc$, "beautify" as beautify
doc$=string$(eval$(buffer("base1.xml")) as UTF8dec)
with xml, "firstchild" as firstchild
child=firstchild
with child,"attr" as attr$()
inventory alfa
do
if not exist(alfa, @tag$()) then
append alfa, @tag$():=child
else
return alfa, @tag$():=child
end if
Method xml, "EndOffChilds", &child as ok
when ok
sort alfa
k=each(alfa)
while k
child=eval(k)
PrintConsoleLn(attr$("name")+","+@tag$()+","+attr$("date"))
end while
declare xml nothing
}
module All {
PrintConsoleLn("All entries sorted by date:")
if exist(filename$) else exit
declare xml xmlData
with xml, "xml" as doc$, "beautify" as beautify
doc$=string$(eval$(buffer("base1.xml")) as UTF8dec)
with xml, "firstchild" as firstchild
child=firstchild
with child,"attr" as attr$()
inventory alfa
i=0
do
// prevent same keys using a unique patch key
append alfa, attr$("date")+str$(i,"000000"):=child
i++
Method xml, "EndOffChilds", &child as ok
when ok
sort alfa
k=each(alfa)
while k
child=eval(k)
PrintConsoleLn(attr$("name")+","+@tag$()+","+attr$("date"))
end while
declare xml nothing
}
module add (line$) {
line$=trim$(line$)
if line$="" then exit
declare xml xmlData
with xml, "xml" as doc$, "beautify" as beautify
bom$=str$(format$("\uef\ubb\ubf"))
// len(bom$)=1.5 (1.5*2=3 bytes)
k=0
if exist(filename$) then try {k=filelen(filename$)}
if k<10 then
method xml, "PrepareNodeSimple", "xml" as ProcessInstructions
method xml, "PlaceAttributeToNode", ProcessInstructions, "version", "1.0"
method xml, "PlaceAttributeToNode", ProcessInstructions, "encoding", "utf-8-sig"
method xml, "PlaceProcessingInstructions", ProcessInstructions
method xml, "PrepareNode", "MyFile" as Node
method xml, "InsertNode", Node
else
doc$=string$(eval$(buffer(filename$)) as UTF8dec)
end if
a$=""""+line$
def name$, tag$,date$
do
a$=rightpart$(a$, """") : what$=lcase$(trim$(leftpart$(a$, """")))
if what$="" then exit
a$=rightpart$(a$, """") :par$=leftpart$(a$, """")
select case what$
case "name"
name$=par$
case "tag"
tag$=par$
case "date"
date$=par$
end select
always
if name$<>"" and date$<>"" then
method xml, "PrepareNode", "Row", "" as Node1
method xml, "PlaceAttributeToNode", Node1, "name", name$
if tag$<>"" then method xml, "PlaceAttributeToNode", Node1, "tag", tag$
method xml, "PlaceAttributeToNode", Node1, "date", date$
method xml, "AppendChild", Node1
open filename$ for wide output as #f
print #f, bom$;string$(doc$ as UTF8enc);
close #f
beautify=-4
PrintConsoleLn(doc$)
end if
declare xml nothing
}
declare FreeConsole lib "Kernel32.FreeConsole"
declare GetStdHandle lib "Kernel32.GetStdHandle" {long a}
declare AttachConsole lib "Kernel32.AttachConsole" {long a}
declare CloseHandle lib "Kernel32.CloseHandle" {long a}
declare global WriteCons Lib "Kernel32.WriteConsoleW" {long cons, a$, long n, Long p, long u}
long STD_OUTPUT_HANDLE=-11
global retvalue
buffer clear retvalue as long
ret=AttachConsole(-1)
global m=GetStdHandle(STD_OUTPUT_HANDLE)
if ret=0 then beep: exit
if not islet then
try {
open "tool.bat" for output as #f
print #f, {@}+appdir$+{m2000.exe data {%*}: dir %cd%:load tool
}
close #f
}
PrintConsoleLn("")
dos "tool.bat"
else
read cmd$
cmd$=trim$(cmd$)+" "
select case lcase$(leftpart$(cmd$, " "))
case "add"
add rightpart$(cmd$," ")
case "latest"
latest
case "latest-per-tag"
latestForEachTag
case "all-entries"
all
case else
help()
end select
end if
call void closehandle(m)
call void freeconsole()
 
Sub PrintConsole(a$)
Call Void WriteCons(m, a$, Len(a$), retvalue(0), 0)
End Sub
Sub PrintConsoleLn(a$)
a$+={
}
Call Void WriteCons(m, a$, Len(a$), retvalue(0), 0)
End Sub
// function is static here but can be called from child modules, because there are in the same block of code
// although attr$() must defined in each module. (scope constrain to module block, for local identifiers).
function tag$()
try { // if no tag exist error raised
=attr$("tag")
}
end function
Sub Help()
h$={Commands:
tool add name "anyname" tag "tagtext" date "YYYY.MM.DD.HH:MM"
tool latest
tool latest-per-tag
tool all-entries
}
PrintConsole(h$)
End Sub
}
module interpret1 {
try {interpret}
}
interpret1: end
</syntaxhighlight>
{{out}}
<pre>
first time the program make a tool.bat
>tool.gsb
 
So now we can call the tool bat.
>tool
Commands:
tool add name "anyname" tag "tagtext" date "YYYY.MM.DD.HH:MM"
tool latest
tool latest-per-tag
tool all-entries
 
>tool add name "BOB" tag "EAT A LOT" date "2022.10.21.04:00"
>tool add name "JOHN" tag "DRINK WATER" "date 2022.10.15.12:00"
>tool add name "PAUL" tag "EAT A LOT" date "2022.10.13.22:00"
>tool add name "SUZAN" tag "DRINK WATER" date "2022.10.13.12:00"
>tool add name "PHILIP" tag "DRINK WATER" date "2022.10.13.10:00"
>tool add name "MONDY" tag "EAT A LOT" date "2022.10.10.12:00"
>tool add name "MARY" tag "PIZZA FRIENDLY" date "2022.10.10.12:00"
>tool add name "DONALD" tag "PIZZA FRIENDLY" date "2022.10.10.02:00"
>tool add name "GEORGE" date "2022.11.29.16:55"
 
This is the last print from last tool add:
<?xml version="1.0" encoding="utf-8-sig"?>
<MyFile>
<Row name="BOB" tag="EAT A LOT" date="2022.10.21.04:00"></Row>
<Row name="PAUL" tag="EAT A LOT" date="2022.10.13.22:00"></Row>
<Row name="SUZAN" tag="DRINK WATER" date="2022.10.13.12:00"></Row>
<Row name="PHILIP" tag="DRINK WATER" date="2022.10.13.10:00"></Row>
<Row name="MONDY" tag="EAT A LOT" date="2022.10.10.12:00"></Row>
<Row name="MARY" tag="PIZZA FRIENDLY" date="2022.10.10.12:00"></Row>
<Row name="DONALD" tag="PIZZA FRIENDLY" date="2022.10.10.02:00"></Row>
<Row name="GEORGE" date="2022.11.29.16:55"></Row>
</MyFile>
 
 
>tool latest
The latest entry is:
GEORGE,,2022.11.29.16:55
 
>tool latest-per-tag
latest entry for each tag:
GEORGE,,2022.11.29.16:55
PHILIP,DRINK WATER,2022.10.13.10:00
MONDY,EAT A LOT,2022.10.10.12:00
DONALD,PIZZA FRIENDLY,2022.10.10.02:00
 
>tool all-entries
All entries sorted by date:
DONALD,PIZZA FRIENDLY,2022.10.10.02:00
MONDY,EAT A LOT,2022.10.10.12:00
MARY,PIZZA FRIENDLY,2022.10.10.12:00
PHILIP,DRINK WATER,2022.10.13.10:00
SUZAN,DRINK WATER,2022.10.13.12:00
PAUL,EAT A LOT,2022.10.13.22:00
BOB,EAT A LOT,2022.10.21.04:00
GEORGE,,2022.11.29.16:55
</pre>
 
=={{header|Nim}}==
{{trans|D}}
{{trans|Kotlin}}
There are some important differences with D version and Kotlin versions. Firstly, the way to manage the command arguments is somewhat different. And secondly, the database is stored in JSON format rather than in CSV format. Indeed, if Nim provides a parser of CSV files, it provides better support for JSON with procedures for serialization of Nim objects to JSON and deserialization from JSON to Nim objects. This can be seen in the following program.
 
<syntaxhighlight lang="nim">import algorithm, json, os, strformat, strutils, times
 
const FileName = "simdb.json"
 
type
 
Item = object
name: string
date: string
category: string
 
Database = seq[Item]
 
DbError = object of CatchableError
 
 
proc load(): Database =
if fileExists(FileName):
let node = try: FileName.parseFile()
except JsonParsingError:
raise newException(DbError, getCurrentExceptionMsg())
result = node.to(DataBase)
 
 
proc store(db: Database) =
try:
FileName.writeFile $(%* db)
except IOError:
quit "Unable to save database.", QuitFailure
 
 
proc addItem(args: seq[string]) =
var db = try: load()
except DbError: quit getCurrentExceptionMsg(), QuitFailure
 
let date = now().format("yyyy-MM-dd HH:mm:ss")
let cat = if args.len == 2: args[1] else: "none"
db.add Item(name: args[0], date: date, category: cat)
db.store()
 
 
proc printLatest(args: seq[string]) =
let db = try: load()
except DbError: quit getCurrentExceptionMsg(), QuitFailure
if db.len == 0:
echo "No entries in database."
return
 
# No need to sort db as items are added chronologically.
if args.len == 1:
var found = false
for item in reversed(db):
if item.category == args[0]:
echo item
found = true
break
if not found:
echo &"There are no items for category '{args[0]}'"
else:
echo db[^1]
 
 
proc printAll() =
let db = try: load()
except DbError: quit getCurrentExceptionMsg(), QuitFailure
if db.len == 0:
echo "No entries in database."
return
for item in db:
echo item
 
 
proc printUsage() =
echo &"""
Usage:
{getAppFilename().splitPath().tail} cmd [categoryName]
 
add add item, followed by optional category
latest print last added item(s), followed by optional category
all print all
 
For instance: add "some item name" "some category name"
"""
quit QuitFailure
 
 
if paramCount() notin 1..3: printUsage()
 
var params = commandLineParams()
let command = params[0].toLowerAscii
params.delete(0)
case command
of "add":
if params.len == 0: printUsage()
addItem(params)
of "latest":
if params.len > 1: printUsage()
printLatest(params)
of "all":
if params.len != 0: printUsage()
printAll()</syntaxhighlight>
 
{{out}}
Sample session (same as that of Kotlin).
<pre>$ ./simple_database add item1
$ ./simple_database add item2
$ ./simple_database add item3 cat3
$ ./simple_database add item4 cat3
$ ./simple_database add item5 cat3
$ ./simple_database latest
(name: "item5", date: "2021-04-09 00:31:34", category: "cat3")
$ ./simple_database latest none
(name: "item2", date: "2021-04-09 00:31:08", category: "none")
$ ./simple_database latest cat4
There are no items for category 'cat4'
$ ./simple_database all
(name: "item1", date: "2021-04-09 00:31:03", category: "none")
(name: "item2", date: "2021-04-09 00:31:08", category: "none")
(name: "item3", date: "2021-04-09 00:31:19", category: "cat3")
(name: "item4", date: "2021-04-09 00:31:25", category: "cat3")
(name: "item5", date: "2021-04-09 00:31:34", category: "cat3")</pre>
 
=={{header|Perl}}==
<syntaxhighlight lang="perl">#!/usr/bin/perl
use warnings;
use strict;
use feature qw{ say };
 
use JSON::PP;
use Time::Piece;
 
use constant {
NAME => 0,
CATEGORY => 1,
DATE => 2,
DB => 'simple-db',
};
 
my $operation = shift // "";
 
my %dispatch = (
n => \&add_new,
l => \&print_latest,
L => \&print_latest_for_categories,
a => \&print_all,
);
 
if ($dispatch{$operation}) {
$dispatch{$operation}->(@ARGV);
} else {
die "Invalid option. Use one of n, l, L, a.\n"
}
 
sub add_new {
my ($name, $category, $date) = @_;
my $db = eval { load() } || {};
if (defined $date) {
eval { 'Time::Piece'->strptime($date, '%Y-%m-%d'); 1 }
or die "Invalid date format: YYYY-MM-DD.\n";
 
} else {
$date //= localtime->ymd;
}
 
my @ids = keys %{ $db->{by_id} };
my $max_id = max(num => @ids) || 0;
$db->{by_id}{ ++$max_id } = [ $name, $category, $date ];
save($db);
}
 
sub print_latest {
build_indexes( my $db = load(), 0, 1 );
_print_latest($db);
}
 
sub _print_latest {
my ($db, $category) = @_;
my @dates = keys %{ $db->{by_date} };
@dates = grep {
grep $db->{by_id}{$_}[CATEGORY] eq $category,
@{ $db->{by_date}{$_} };
} @dates if defined $category;
 
my $last_date = max(str => @dates);
say for map $db->{by_id}{$_}[NAME],
grep ! defined $category
|| $db->{by_id}{$_}[CATEGORY] eq $category,
@{ $db->{by_date}{$last_date} };
}
 
sub max {
my $type = shift;
my $max = $_[0];
{ num => sub { $_ > $max },
str => sub { $_ gt $max},
}->{$type}->() and $max = $_
for @_[ 1 .. $#_ ];
return $max
}
 
sub print_latest_for_categories {
build_indexes( my $db = load(), 1, 1 );
 
for my $category (sort keys %{ $db->{by_category} }){
say "* $category";
_print_latest($db, $category);
}
}
 
sub print_all {
build_indexes( my $db = load(), 0, 1 );
 
for my $date (sort keys %{ $db->{by_date} }) {
for my $id (@{ $db->{by_date}{$date} }) {
say $db->{by_id}{$id}[NAME];
}
}
}
 
sub load {
open my $in, '<', DB or die "Can't open database: $!\n";
local $/;
return { by_id => decode_json(<$in>) };
}
 
sub save {
my ($db) = @_;
open my $out, '>', DB or die "Can't save database: $!\n";
print {$out} encode_json($db->{by_id});
close $out;
}
 
sub build_indexes {
my ($db, $by_category, $by_date) = @_;
for my $id (keys %{ $db->{by_id} }) {
push @{ $db->{by_category}{ $db->{by_id}{$id}[CATEGORY] } }, $id
if $by_category;
push @{ $db->{by_date}{ $db->{by_id}{$id}[DATE] } }, $id
if $by_date;
}
}</syntaxhighlight>
Sample session<pre> ~ $ db.pl n 'Donald Trump' Republican 2017-01-20
~ $ db.pl n 'Barack Obama' Democratic 2009-01-20
~ $ db.pl n 'Bill Clinton' Democratic 1993-01-20
~ $ db.pl n 'George W. Bush' Republican 2001-01-20
~ $ db.pl a
Bill Clinton
George W. Bush
Barack Obama
Donald Trump
~ $ db.pl l
Donald Trump
~ $ db.pl L
* Democratic
Barack Obama
* Republican
Donald Trump</pre>
 
=={{header|Phix}}==
<!--<syntaxhighlight lang="phix">(notonline)-->
<span style="color: #000080;font-style:italic;">--
-- demo\rosetta\Simple_db.exw
-- ==========================
--</span>
<span style="color: #008080;">without</span> <span style="color: #008080;">js</span> <span style="color: #000080;font-style:italic;">-- (file i/o, gets(0), getenv)</span>
<span style="color: #008080;">include</span> <span style="color: #004080;">timedate</span><span style="color: #0000FF;">.</span><span style="color: #000000;">e</span>
<span style="color: #008080;">constant</span> <span style="color: #000000;">filename</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">getenv</span><span style="color: #0000FF;">(</span><span style="color: #008080;">iff</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">platform</span><span style="color: #0000FF;">()=</span><span style="color: #004600;">WINDOWS</span><span style="color: #0000FF;">?</span><span style="color: #008000;">"APPDATA"</span><span style="color: #0000FF;">:</span><span style="color: #008000;">"HOME"</span><span style="color: #0000FF;">))&</span><span style="color: #008000;">"/simple_db.csv"</span>
<span style="color: #008080;">procedure</span> <span style="color: #000000;">add</span><span style="color: #0000FF;">(</span><span style="color: #004080;">sequence</span> <span style="color: #000000;">cmd</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">if</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cmd</span><span style="color: #0000FF;">)=</span><span style="color: #000000;">0</span>
<span style="color: #008080;">or</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cmd</span><span style="color: #0000FF;">)></span><span style="color: #000000;">2</span> <span style="color: #008080;">then</span>
<span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"usage: add name [cat]\n"</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">else</span>
<span style="color: #004080;">string</span> <span style="color: #000000;">name</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">cmd</span><span style="color: #0000FF;">[</span><span style="color: #000000;">1</span><span style="color: #0000FF;">],</span>
<span style="color: #000000;">cat</span> <span style="color: #0000FF;">=</span> <span style="color: #008080;">iff</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cmd</span><span style="color: #0000FF;">)=</span><span style="color: #000000;">2</span><span style="color: #0000FF;">?</span><span style="color: #000000;">cmd</span><span style="color: #0000FF;">[</span><span style="color: #000000;">2</span><span style="color: #0000FF;">]:</span><span style="color: #008000;">"none"</span><span style="color: #0000FF;">)</span>
<span style="color: #000000;">datestr</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">format_timedate</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">date</span><span style="color: #0000FF;">(),</span><span style="color: #008000;">"YYYY/MM/DD h:mmpm"</span><span style="color: #0000FF;">)</span>
<span style="color: #004080;">integer</span> <span style="color: #000000;">fn</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">open</span><span style="color: #0000FF;">(</span><span style="color: #000000;">filename</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"a"</span><span style="color: #0000FF;">)</span>
<span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">fn</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"%s,%s,%s\n"</span><span style="color: #0000FF;">,{</span><span style="color: #000000;">name</span><span style="color: #0000FF;">,</span><span style="color: #000000;">cat</span><span style="color: #0000FF;">,</span><span style="color: #000000;">datestr</span><span style="color: #0000FF;">})</span>
<span style="color: #7060A8;">close</span><span style="color: #0000FF;">(</span><span style="color: #000000;">fn</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span>
<span style="color: #008080;">procedure</span> <span style="color: #000000;">last</span><span style="color: #0000FF;">(</span><span style="color: #004080;">sequence</span> <span style="color: #000000;">cmd</span><span style="color: #0000FF;">)</span>
<span style="color: #004080;">integer</span> <span style="color: #000000;">fn</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">open</span><span style="color: #0000FF;">(</span><span style="color: #000000;">filename</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"r"</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">if</span> <span style="color: #000000;">fn</span><span style="color: #0000FF;">=-</span><span style="color: #000000;">1</span> <span style="color: #008080;">then</span>
<span style="color: #7060A8;">puts</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"file not found\n"</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">return</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #004080;">integer</span> <span style="color: #000000;">lc</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cmd</span><span style="color: #0000FF;">)</span>
<span style="color: #004080;">string</span> <span style="color: #000000;">last</span> <span style="color: #0000FF;">=</span> <span style="color: #008080;">iff</span><span style="color: #0000FF;">(</span><span style="color: #000000;">lc</span><span style="color: #0000FF;">?</span><span style="color: #008000;">"&lt;no entries for that category&gt;\n"</span><span style="color: #0000FF;">:</span><span style="color: #008000;">"&lt;empty&gt;\n"</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">while</span> <span style="color: #000000;">1</span> <span style="color: #008080;">do</span>
<span style="color: #004080;">object</span> <span style="color: #000000;">line</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">gets</span><span style="color: #0000FF;">(</span><span style="color: #000000;">fn</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">if</span> <span style="color: #004080;">atom</span><span style="color: #0000FF;">(</span><span style="color: #000000;">line</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span> <span style="color: #008080;">exit</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #008080;">if</span> <span style="color: #000000;">lc</span><span style="color: #0000FF;">=</span><span style="color: #000000;">0</span> <span style="color: #008080;">or</span> <span style="color: #7060A8;">split</span><span style="color: #0000FF;">(</span><span style="color: #000000;">line</span><span style="color: #0000FF;">,</span><span style="color: #008000;">','</span><span style="color: #0000FF;">)[</span><span style="color: #000000;">2</span><span style="color: #0000FF;">]=</span><span style="color: #000000;">cmd</span><span style="color: #0000FF;">[</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]</span> <span style="color: #008080;">then</span>
<span style="color: #000000;">last</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">line</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">while</span>
<span style="color: #7060A8;">puts</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">last</span><span style="color: #0000FF;">)</span>
<span style="color: #7060A8;">close</span><span style="color: #0000FF;">(</span><span style="color: #000000;">fn</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span>
<span style="color: #004080;">sequence</span> <span style="color: #000000;">dates</span>
<span style="color: #008080;">function</span> <span style="color: #000000;">by_date</span><span style="color: #0000FF;">(</span><span style="color: #004080;">integer</span> <span style="color: #000000;">d1</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">integer</span> <span style="color: #000000;">d2</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">return</span> <span style="color: #7060A8;">compare</span><span style="color: #0000FF;">(</span><span style="color: #000000;">dates</span><span style="color: #0000FF;">[</span><span style="color: #000000;">d1</span><span style="color: #0000FF;">],</span><span style="color: #000000;">dates</span><span style="color: #0000FF;">[</span><span style="color: #000000;">d2</span><span style="color: #0000FF;">])</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
<span style="color: #008080;">procedure</span> <span style="color: #000000;">sort_by_date</span><span style="color: #0000FF;">()</span>
<span style="color: #000080;font-style:italic;">-- (simple_db.csv should be edited manually to prove the date sort works)</span>
<span style="color: #004080;">integer</span> <span style="color: #000000;">fn</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">open</span><span style="color: #0000FF;">(</span><span style="color: #000000;">filename</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"r"</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">if</span> <span style="color: #000000;">fn</span><span style="color: #0000FF;">=-</span><span style="color: #000000;">1</span> <span style="color: #008080;">then</span>
<span style="color: #7060A8;">puts</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"file not found\n"</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">return</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #004080;">sequence</span> <span style="color: #000000;">lines</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{}</span>
<span style="color: #000000;">dates</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{}</span>
<span style="color: #008080;">while</span> <span style="color: #000000;">1</span> <span style="color: #008080;">do</span>
<span style="color: #004080;">object</span> <span style="color: #000000;">line</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">gets</span><span style="color: #0000FF;">(</span><span style="color: #000000;">fn</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">if</span> <span style="color: #004080;">atom</span><span style="color: #0000FF;">(</span><span style="color: #000000;">line</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">then</span> <span style="color: #008080;">exit</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #000000;">lines</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">append</span><span style="color: #0000FF;">(</span><span style="color: #000000;">lines</span><span style="color: #0000FF;">,</span><span style="color: #000000;">line</span><span style="color: #0000FF;">)</span>
<span style="color: #000000;">dates</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">append</span><span style="color: #0000FF;">(</span><span style="color: #000000;">dates</span><span style="color: #0000FF;">,</span><span style="color: #7060A8;">split</span><span style="color: #0000FF;">(</span><span style="color: #000000;">line</span><span style="color: #0000FF;">,</span><span style="color: #008000;">','</span><span style="color: #0000FF;">)[</span><span style="color: #000000;">3</span><span style="color: #0000FF;">])</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">while</span>
<span style="color: #7060A8;">close</span><span style="color: #0000FF;">(</span><span style="color: #000000;">fn</span><span style="color: #0000FF;">)</span>
<span style="color: #004080;">sequence</span> <span style="color: #000000;">tags</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">custom_sort</span><span style="color: #0000FF;">(</span><span style="color: #000000;">by_date</span><span style="color: #0000FF;">,</span><span style="color: #7060A8;">tagset</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">lines</span><span style="color: #0000FF;">)))</span>
<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">tags</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span>
<span style="color: #7060A8;">puts</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">lines</span><span style="color: #0000FF;">[</span><span style="color: #000000;">tags</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]])</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span>
<span style="color: #008080;">procedure</span> <span style="color: #000000;">process</span><span style="color: #0000FF;">(</span><span style="color: #004080;">sequence</span> <span style="color: #000000;">cmd</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">switch</span> <span style="color: #000000;">cmd</span><span style="color: #0000FF;">[</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]</span> <span style="color: #008080;">do</span>
<span style="color: #008080;">case</span> <span style="color: #008000;">"add"</span><span style="color: #0000FF;">:</span> <span style="color: #000000;">add</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cmd</span><span style="color: #0000FF;">[</span><span style="color: #000000;">2</span><span style="color: #0000FF;">..$])</span>
<span style="color: #008080;">case</span> <span style="color: #008000;">"last"</span><span style="color: #0000FF;">:</span> <span style="color: #000000;">last</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cmd</span><span style="color: #0000FF;">[</span><span style="color: #000000;">2</span><span style="color: #0000FF;">..$])</span>
<span style="color: #008080;">case</span> <span style="color: #008000;">"sort"</span><span style="color: #0000FF;">:</span> <span style="color: #000000;">sort_by_date</span><span style="color: #0000FF;">()</span>
<span style="color: #008080;">default</span><span style="color: #0000FF;">:</span> <span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"unknown command: %s\n"</span><span style="color: #0000FF;">,{</span><span style="color: #000000;">cmd</span><span style="color: #0000FF;">[</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]})</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">switch</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span>
<span style="color: #008080;">constant</span> <span style="color: #000000;">helptext</span> <span style="color: #0000FF;">=</span> <span style="color: #008000;">"""
p demo\rosetta\Simple_db -- interactive mode, commands as below
p demo\rosetta\Simple_db add name [cat] -- add entry
p demo\rosetta\Simple_db last [cat] -- show last entry [in specified category]
p demo\rosetta\Simple_db sort -- show full list sorted by date
"""</span>
<span style="color: #004080;">sequence</span> <span style="color: #000000;">cl</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">command_line</span><span style="color: #0000FF;">()</span>
<span style="color: #008080;">if</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cl</span><span style="color: #0000FF;">)<</span><span style="color: #000000;">3</span> <span style="color: #008080;">then</span>
<span style="color: #000080;font-style:italic;">-- interactive mode</span>
<span style="color: #7060A8;">puts</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">helptext</span><span style="color: #0000FF;">)</span>
<span style="color: #008080;">while</span> <span style="color: #000000;">1</span> <span style="color: #008080;">do</span>
<span style="color: #7060A8;">puts</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"&gt;"</span><span style="color: #0000FF;">)</span>
<span style="color: #004080;">object</span> <span style="color: #000000;">line</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">trim</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">gets</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">))</span>
<span style="color: #008080;">if</span> <span style="color: #004080;">atom</span><span style="color: #0000FF;">(</span><span style="color: #000000;">line</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">or</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">line</span><span style="color: #0000FF;">)=</span><span style="color: #000000;">0</span> <span style="color: #008080;">then</span> <span style="color: #008080;">exit</span> <span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<span style="color: #7060A8;">puts</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"\n"</span><span style="color: #0000FF;">)</span>
<span style="color: #000000;">process</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">split</span><span style="color: #0000FF;">(</span><span style="color: #000000;">line</span><span style="color: #0000FF;">))</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">while</span>
<span style="color: #008080;">else</span>
<span style="color: #000000;">process</span><span style="color: #0000FF;">(</span><span style="color: #000000;">cl</span><span style="color: #0000FF;">[</span><span style="color: #000000;">3</span><span style="color: #0000FF;">..$])</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
<!--</syntaxhighlight>-->
Sample session
<pre>
C:\Program Files (x86)\Phix>p demo\rosetta\simple_db
p demo\rosetta\Simple_db -- interactive mode, commands as below
p demo\rosetta\Simple_db add name [cat] -- add entry
p demo\rosetta\Simple_db last [cat] -- show last entry [in specified category]
p demo\rosetta\Simple_db sort -- show full list sorted by date
>sort
fred,none,2016/07/25 12:30pm
cliff,none,2016/07/25 12:31pm
barney,none,2016/07/25 12:32pm
one,two,2016/07/25 12:33pm
>add three four
>sort
fred,none,2016/07/25 12:30pm
cliff,none,2016/07/25 12:31pm
barney,none,2016/07/25 12:32pm
one,two,2016/07/25 12:33pm
three,four,2016/07/25 12:39pm
>last
three,four,2016/07/25 12:39pm
>last one
<no entries for that category>
>last two
one,two,2016/07/25 12:33pm
>
</pre>
 
=={{header|PicoLisp}}==
The '[http://software-lab.de/doc/refR.html#rc rc]' resource file handling function is used typically for such tasks. It also takes care of proper locking and protection.
<langsyntaxhighlight PicoLisplang="picolisp">#!/usr/bin/pil
 
(de usage ()
Line 1,030 ⟶ 3,700:
(T (usage)) ) )
 
(bye)</langsyntaxhighlight>
Test:
<pre>$ sdb CDs add "Title 1" "Category 1" 2011-11-13
Line 1,054 ⟶ 3,724:
 
=={{header|Pike}}==
{{trans|Common Lisp}} (simplified)
<langsyntaxhighlight Pikelang="pike">mapping db = ([]);
 
mapping make_episode(string series, string title, string episode, array date)
Line 1,208 ⟶ 3,878:
else
watch_list(db);
}</langsyntaxhighlight>
 
=={{header|PowerShell}}==
<syntaxhighlight lang="powershell">
function db
{
[CmdletBinding(DefaultParameterSetName="None")]
[OutputType([PSCustomObject])]
Param
(
[Parameter(Mandatory=$false,
Position=0,
ParameterSetName="Add a new entry")]
[string]
$Path = ".\SimpleDatabase.csv",
 
[Parameter(Mandatory=$true,
ParameterSetName="Add a new entry")]
[string]
$Name,
 
[Parameter(Mandatory=$true,
ParameterSetName="Add a new entry")]
[string]
$Category,
 
[Parameter(Mandatory=$true,
ParameterSetName="Add a new entry")]
[datetime]
$Birthday,
 
[Parameter(ParameterSetName="Print the latest entry")]
[switch]
$Latest,
 
[Parameter(ParameterSetName="Print the latest entry for each category")]
[switch]
$LatestByCategory,
 
[Parameter(ParameterSetName="Print all entries sorted by a date")]
[switch]
$SortedByDate
)
 
if (-not (Test-Path -Path $Path))
{
'"Name","Category","Birthday"' | Out-File -FilePath $Path
}
 
$db = Import-Csv -Path $Path | Foreach-Object {
$_.Birthday = $_.Birthday -as [datetime]
$_
}
 
switch ($PSCmdlet.ParameterSetName)
{
"Add a new entry"
{
[PSCustomObject]@{Name=$Name; Category=$Category; Birthday=$Birthday} | Export-Csv -Path $Path -Append
}
"Print the latest entry"
{
$db[-1]
}
"Print the latest entry for each category"
{
($db | Group-Object -Property Category).Name | ForEach-Object {($db | Where-Object -Property Category -Contains $_)[-1]}
}
"Print all entries sorted by a date"
{
$db | Sort-Object -Property Birthday
}
Default
{
$db
}
}
}
 
db -Name Bev -Category friend -Birthday 3/3/1983
db -Name Bob -Category family -Birthday 7/19/1987
db -Name Gill -Category friend -Birthday 12/9/1986
db -Name Gail -Category family -Birthday 2/11/1986
db -Name Vince -Category family -Birthday 3/10/1960
db -Name Wayne -Category coworker -Birthday 5/29/1962
</syntaxhighlight>
Here is the data from the CSV file as a PowerShell Object:
<syntaxhighlight lang="powershell">
db
</syntaxhighlight>
{{Out}}
<pre>
Name Category Birthday
---- -------- --------
Bev friend 3/3/1983 12:00:00 AM
Bob family 7/19/1987 12:00:00 AM
Gill friend 12/9/1986 12:00:00 AM
Gail family 2/11/1986 12:00:00 AM
Vince family 3/10/1960 12:00:00 AM
Wayne coworker 5/29/1962 12:00:00 AM
</pre>
The latest entry:
<syntaxhighlight lang="powershell">
db -Latest
</syntaxhighlight>
{{Out}}
<pre>
Name Category Birthday
---- -------- --------
Wayne coworker 5/29/1962 12:00:00 AM
</pre>
The latest entries by category:
<syntaxhighlight lang="powershell">
db -LatestByCategory
</syntaxhighlight>
{{Out}}
<pre>
Name Category Birthday
---- -------- --------
Gill friend 12/9/1986 12:00:00 AM
Vince family 3/10/1960 12:00:00 AM
Wayne coworker 5/29/1962 12:00:00 AM
</pre>
The database sorted on the Birthday property:
<syntaxhighlight lang="powershell">
db -SortedByDate
</syntaxhighlight>
{{Out}}
<pre>
Name Category Birthday
---- -------- --------
Vince family 3/10/1960 12:00:00 AM
Wayne coworker 5/29/1962 12:00:00 AM
Bev friend 3/3/1983 12:00:00 AM
Gail family 2/11/1986 12:00:00 AM
Gill friend 12/9/1986 12:00:00 AM
Bob family 7/19/1987 12:00:00 AM
</pre>
 
=={{header|Python}}==
<syntaxhighlight lang="python">#!/usr/bin/python3
 
'''\
Simple database for: http://rosettacode.org/wiki/Simple_database
 
'''
 
import argparse
from argparse import Namespace
import datetime
import shlex
 
 
def parse_args():
'Set up, parse, and return arguments'
parser = argparse.ArgumentParser(epilog=globals()['__doc__'])
 
parser.add_argument('command', choices='add pl plc pa'.split(),
help='''\
add: Add a new entry
pl: Print the latest entry
plc: Print the latest entry for each category/tag
pa: Print all entries sorted by a date''')
parser.add_argument('-d', '--description',
help='A description of the item. (e.g., title, name)')
parser.add_argument('-t', '--tag',
help=('''A category or tag (genre, topic, relationship '''
'''such as “friend” or “family”)'''))
parser.add_argument('-f', '--field', nargs=2, action='append',
help='Other optional fields with value (can be repeated)')
 
return parser
 
def do_add(args, dbname):
'Add a new entry'
if args.description is None:
args.description = ''
if args.tag is None:
args.tag = ''
del args.command
print('Writing record to %s' % dbname)
with open(dbname, 'a') as db:
db.write('%r\n' % args)
def do_pl(args, dbname):
'Print the latest entry'
print('Getting last record from %s' % dbname)
with open(dbname, 'r') as db:
for line in db: pass
record = eval(line)
del record._date
print(str(record))
def do_plc(args, dbname):
'Print the latest entry for each category/tag'
print('Getting latest record for each tag from %s' % dbname)
with open(dbname, 'r') as db:
records = [eval(line) for line in db]
tags = set(record.tag for record in records)
records.reverse()
for record in records:
if record.tag in tags:
del record._date
print(str(record))
tags.discard(record.tag)
if not tags: break
 
def do_pa(args, dbname):
'Print all entries sorted by a date'
print('Getting all records by date from %s' % dbname)
with open(dbname, 'r') as db:
records = [eval(line) for line in db]
for record in records:
del record._date
print(str(record))
 
def test():
import time
parser = parse_args()
for cmdline in [
"""-d Book -f title 'Windy places' -f type hardback --tag DISCOUNT add""",
"""-d Book -f title 'RC spammers' -f type paperback -t DISCOUNT add""",
"""-d Book -f title 'Splat it' -f type hardback -f special 'first edition' -t PREMIUM add""",
"""pl""",
"""plc""",
]:
args = parser.parse_args(shlex.split(cmdline))
now = datetime.datetime.utcnow()
args._date = now.isoformat()
do_command[args.command](args, dbname)
time.sleep(0.5)
 
 
do_command = dict(add=do_add, pl=do_pl, plc=do_plc, pa=do_pa)
dbname = '_simple_db_db.py'
 
 
if __name__ == '__main__':
if 0:
test()
else:
parser = parse_args()
args = parser.parse_args()
now = datetime.datetime.utcnow()
args._date = now.isoformat()
do_command[args.command](args, dbname)</syntaxhighlight>
 
;Sample session (Unix):
<pre>paddy3118:~$ ./simple_db.py -h
usage: simple_db.py [-h] [-d DESCRIPTION] [-t TAG] [-f FIELD FIELD]
{add,pl,plc,pa}
 
positional arguments:
{add,pl,plc,pa} add: Add a new entry pl: Print the latest entry plc:
Print the latest entry for each category/tag pa: Print
all entries sorted by a date
 
optional arguments:
-h, --help show this help message and exit
-d DESCRIPTION, --description DESCRIPTION
A description of the item. (e.g., title, name)
-t TAG, --tag TAG A category or tag (genre, topic, relationship such as
“friend” or “family”)
-f FIELD FIELD, --field FIELD FIELD
Other optional fields with value (can be repeated)
 
Simple database for: http://rosettacode.org/wiki/Simple_database
paddy3118:~$ ./simple_db.py -d Book -f title 'Windy places' -f type hardback --tag DISCOUNT add
Writing record to _simple_db_db.py
paddy3118:~$ ./simple_db.py -d Book -f title 'RC spammers' -f type paperback -t DISCOUNT add
Writing record to _simple_db_db.py
paddy3118:~$ ./simple_db.py -d Book -f title 'Splat it' -f type hardback -f special 'first edition' -t PREMIUM add
Writing record to _simple_db_db.py
paddy3118:~$ ./simple_db.py pl
Getting last record from _simple_db_db.py
Namespace(description='Book', field=[['title', 'Splat it'], ['type', 'hardback'], ['special', 'first edition']], tag='PREMIUM')
paddy3118:~$ ./simple_db.py plc
Getting latest record for each tag from _simple_db_db.py
Namespace(description='Book', field=[['title', 'Splat it'], ['type', 'hardback'], ['special', 'first edition']], tag='PREMIUM')
Namespace(description='Book', field=[['title', 'RC spammers'], ['type', 'paperback']], tag='DISCOUNT')
paddy3118:~$ ./simple_db.py pa
Getting all records by date from _simple_db_db.py
Namespace(description='Book', field=[['title', 'Windy places'], ['type', 'hardback']], tag='DISCOUNT')
Namespace(description='Book', field=[['title', 'RC spammers'], ['type', 'paperback']], tag='DISCOUNT')
Namespace(description='Book', field=[['title', 'Splat it'], ['type', 'hardback'], ['special', 'first edition']], tag='PREMIUM')
paddy3118:~$
paddy3118:~$ cat _simple_db_db.py
Namespace(_date='2012-08-18T06:02:44.947091', description='Book', field=[['title', 'Windy places'], ['type', 'hardback']], tag='DISCOUNT')
Namespace(_date='2012-08-18T06:03:11.477429', description='Book', field=[['title', 'RC spammers'], ['type', 'paperback']], tag='DISCOUNT')
Namespace(_date='2012-08-18T06:03:34.319799', description='Book', field=[['title', 'Splat it'], ['type', 'hardback'], ['special', 'first edition']], tag='PREMIUM')
paddy3118:~$ </pre>
 
=={{header|Racket}}==
<syntaxhighlight lang="racket">
#!/usr/bin/env racket
#lang racket
 
(define (*write file data) ; write data in human readable format (sexpr/line)
(with-output-to-file file #:exists 'replace
(lambda () (for ([x data]) (printf "~s\n" x)))))
(define *read file->list) ; read our "human readable format"
 
(command-line
#:once-any
[("-a") file title category date "Add an entry"
(*write file `(,@(*read file) (,title ,category ,date)))]
[("-d") file title "Delete an entry (all matching)"
(*write file (filter-not (lambda (x) (equal? (car x) title)) (*read file)))]
[("-p") file mode "Print entries, mode = latest, latest/cat, all, by-date"
(define data (*read file))
(define (show item)
(match item [(list title cat date) (printf "[~a] ~a; ~a\n" cat title date)]))
(case (string->symbol mode)
[(all) (for-each show data)]
[(by-date) (for-each show (sort data string<? #:key cadr))]
[(latest) (show (last data))]
[(latest/cat)
(define (last/cat c) (for/last ([x data] #:when (equal? c (cadr x))) x))
(for-each (compose1 show last/cat) (remove-duplicates (map cadr data)))]
[else (error 'sdb "bad printout mode")])])
</syntaxhighlight>
 
Sample run:
<pre>
$ ./sdb -h
sdb [ <option> ... ]
where <option> is one of
/ -a <file> <title> <category> <date> : Add an entry
| -d <file> <title> : Delete an entry (all matching)
\ -p <file> <mode> : Print entries, mode = latest, latest/cat, all
--help, -h : Show this help
-- : Do not treat any remaining argument as a switch (at this level)
/|\ Brackets indicate mutually exclusive options.
Multiple single-letter switches can be combined after one `-'; for
example: `-h-' is the same as `-h --'
$ ./sdb -a Stuffs A-Book books 2013-01-01
$ ./sdb -a Stuffs Another-Book books 2013-01-02
$ ./sdb -a Stuffs Some-CD cds 2013-01-03
$ ./sdb -a Stuffs A-Bad-CD cds 2013-01-04
$ ./sdb -p Stuffs all
[books] A-Book; 2013-01-01
[books] Another-Book; 2013-01-02
[cds] Some-CD; 2013-01-03
[cds] A-Bad-CD; 2013-01-04
$ ./sdb -p Stuffs latest
[cds] A-Bad-CD; 2013-01-04
$ ./sdb -p Stuffs latest/cat
[books] Another-Book; 2013-01-02
[cds] A-Bad-CD; 2013-01-04
$ ./sdb -d Stuffs A-Bad-CD
$ ./sdb -p Stuffs by-date
[books] A-Book; 2013-01-01
[books] Another-Book; 2013-01-02
[cds] Some-CD; 2013-01-03
</pre>
 
=={{header|Raku}}==
(formerly Perl 6)
A generic client/server JSON database.<br>
<b>server.raku:</b>
<syntaxhighlight lang="raku" line>#!/usr/bin/env raku
use JSON::Fast ;
sub MAIN( :$server='0.0.0.0', :$port=3333, :$dbfile='db' ) {
my %db;
my %index;
my $dbdata = slurp "$dbfile.json" ;
my $indexdata = slurp "{$dbfile}_index.json" ;
%db = from-json($dbdata) if $dbdata ;
%index = from-json($indexdata) if $indexdata ;
react {
whenever IO::Socket::Async.listen( $server , $port ) -> $conn {
whenever $conn.Supply.lines -> $line {
my %response = 'status' => '' ;
my $msg = from-json $line ;
say $msg.perl ;
given $msg<function> {
when 'set' {
%db{ $msg<topic> } = $msg<message> ;
%response<status> = 'ok' ;
%index<last_> = $msg<topic> ;
for %index<keys_>.keys -> $key {
if $msg<message>{$key} {
%index<lastkey_>{ $key }{ $msg<message>{$key} } = $msg<topic> ;
%index<idx_>{ $key }{ $msg<message>{$key} }{ $msg<topic> } = 1 ;
}
}
spurt "$dbfile.json", to-json(%db);
spurt "{$dbfile}_index.json", to-json(%index);
}
when 'get' {
%response<topic> = $msg<topic> ;
%response<message> = %db{ $msg<topic> } ;
%response<status> = 'ok' ;
}
when 'dump' {
%response{'data'} = %db ;
%response<status> = 'ok' ;
}
when 'dumpindex' {
%response{'data'} = %index ;
%response<status> = 'ok' ;
}
when 'delete' {
%db{ $msg<topic> }:delete;
%response<status> = 'ok' ;
spurt "$dbfile.json", to-json(%db);
reindex();
}
when 'addindex' {
%response<status> = 'ok' ;
%index<keys_>{ $msg<key>} =1 ;
reindex();
}
when 'reportlast' {
%response{'data'} = %db{%index<last_>} ;
%response<status> = 'ok' ;
}
when 'reportlastindex' {
%response<key> = $msg<key> ;
for %index<lastkey_>{$msg<key>}.keys -> $value {
#%response{'data'}.push: %db{ %index<lastkey_>{ $msg<key> }{ $value } } ;
%response{'data'}{$value} = %db{ %index<lastkey_>{ $msg<key> }{ $value } } ;
}
%response<status> = 'ok' ;
}
when 'reportindex' {
%response<status> = 'ok' ;
for %index<idx_>{$msg<key>}.keys.sort -> $value {
for %index<idx_>{ $msg<key> }{ $value }.keys.sort -> $topic {
%response<data>.push: %db{ $topic } ;
#%response<data>{$value} = %db{ $topic } ;
}
}
}
when 'commit' {
spurt "$dbfile.json", to-json(%db);
spurt "{$dbfile}_index.json", to-json(%index);
%response<status> = 'ok' ;
}
default {
%response<status> = 'error';
%response<error> = 'no function or not supported';
}
}
$conn.print( to-json(%response, :!pretty) ~ "\n" ) ;
LAST { $conn.close ; }
QUIT { default { $conn.close ; say "oh no, $_";}}
CATCH { default { say .^name, ': ', .Str , " handled in $?LINE";}}
}
}
}
sub reindex {
%index<idx_>:delete;
for %db.keys -> $topic {
my $msg = %db{$topic} ;
for %index<keys_>.keys -> $key {
if $msg{$key} {
%index<idx_>{ $key }{ $msg{$key} }{ $topic } = 1 ;
}
}
}
spurt "{$dbfile}_index.json", to-json(%index) ;
}
}</syntaxhighlight>
<b>client.raku:</b>
<syntaxhighlight lang="raku" line>#!/usr/bin/env raku
use JSON::Fast ;
multi MAIN('set', $topic, $message='', :$server='localhost', :$port='3333', :$json='') {
my %msg = function => 'set' , topic=> $topic , message=> $message ;
%msg{"message"} = from-json( $json ) if $json ;
sendmsg( %msg , $server, $port) ;
}
multi MAIN('add', $topic, $json, :$server='localhost', :$port='3333' ) {
my %msg = function => 'set' , topic=> $topic;
%msg{"message"} = from-json( $json ) if $json ;
sendmsg( %msg , $server, $port) ;
}
multi MAIN('get', $topic, :$server='localhost', :$port='3333') {
my %msg = function => 'get' , topic=> $topic ;
sendmsg( %msg , $server, $port) ;
}
multi MAIN('delete', $topic, :$server='localhost', :$port='3333') {
my %msg = function => 'delete' , topic=> $topic ;
sendmsg( %msg , $server, $port) ;
}
multi MAIN('dump', :$server='localhost', :$port='3333') {
my %msg = function => 'dump' ;
sendmsg( %msg , $server, $port) ;
}
multi MAIN('addindex', $key, :$server='localhost', :$port='3333') {
my %msg = function => 'addindex', key => $key ;
sendmsg( %msg , $server, $port) ;
}
multi MAIN('reportindex', $key, :$server='localhost', :$port='3333') {
my %msg = function => 'reportindex', key => $key ;
sendmsg( %msg , $server, $port) ;
}
multi MAIN('reportlastindex', $key, :$server='localhost', :$port='3333') {
my %msg = function => 'reportlastindex', key => $key ;
sendmsg( %msg , $server, $port) ;
}
multi MAIN('reportlast', :$server='localhost', :$port='3333') {
my %msg = function => 'reportlast' ;
sendmsg( %msg , $server, $port) ;
}
sub sendmsg( %msg , $server, $port){
my $conn = await IO::Socket::Async.connect( $server , $port );
$conn.print: to-json( %msg,:!pretty)~"\n";
react {
whenever $conn.Supply -> $data {
print $data;
$conn.close;
}
}
}</syntaxhighlight>
Example:
<pre>./client.raku addindex constructor
./client.raku addindex date
 
./client.raku add 2007 '{"date":"2007-11-04","constructor":"Ducati","name":"Casey Stoner"}'
./client.raku add 2008 '{"date":"2008-10-26","constructor":"Yamaha","name":"Valentino Rossi"}'
./client.raku add 2009 '{"date":"2009-11-08","constructor":"Yamaha","name":"Valentino Rossi"}'
./client.raku add 2010 '{"date":"2010-11-17","constructor":"Yamaha","name":"Jorge Lorenzo"}'
./client.raku add 2011 '{"date":"2011-11-06","constructor":"Honda","name":"Casey Stoner"}'
./client.raku add 2012 '{"date":"2012-11-11","constructor":"Yamaha","name":"Jorge Lorenzo"}'
./client.raku add 2013 '{"date":"2013-11-10","constructor":"Honda","name":"Marc Márquez"}'
./client.raku add 2014 '{"date":"2014-11-09","constructor":"Honda","name":"Marc Márquez"}'
./client.raku add 2015 '{"date":"2015-11-08","constructor":"Yamaha","name":"Jorge Lorenzo"}'
./client.raku add 2016 '{"date":"2016-11-13","constructor":"Honda","name":"Marc Márquez"}'
./client.raku add 2017 '{"date":"2017-11-12","constructor":"Honda","name":"Marc Márquez"}'
 
./client.raku reportlast
./client.raku reportlastindex constructor
./client.raku reportindex date</pre>
 
=={{header|REBOL}}==
<syntaxhighlight lang="rebol">rebol [author: "Nick Antonaccio"]
write/append %rdb "" db: load %rdb
switch system/options/args/1 [
"new" [write/append %rdb rejoin [now " " mold/only next system/options/args newline]]
"latest" [print copy/part tail sort/skip db 4 -4]
"latestcat" [
foreach cat unique extract at db 3 4 [
t: copy []
foreach [a b c d] db [if c = cat [append t reduce [a b c d]]]
print copy/part tail sort/skip t 4 -4
]
]
"sort" [probe sort/skip db 4]
]
halt</syntaxhighlight>
 
=={{header|REXX}}==
<syntaxhighlight lang="rexx">/* REXX ---------------------------------------------------------------
* 05.10.2014
*--------------------------------------------------------------------*/
x05='05'x
mydb='sidb.txt'
Say 'Enter your commands, ?, or end'
Do Forever
Parse Pull l
Parse Var l command text
Select
When command='?' Then
Call help
When command='add' Then Do
Parse Var text item ',' category ',' date
If date='' Then
date=date('S') /*yyyymmdd*/
Say 'adding item' item'/'category 'dated' date
Call lineout mydb,date item x05 category
End
When command='latest' Then Do
Call lineout mydb
Parse Var text category
hidt='00000000'
ol=''
Do While lines(mydb)>0
l=linein(mydb)
Parse Var l dt a (x05) b
If category=''|,
category='-' & b='' |,
b=category Then Do
If dt>>hidt Then Do
ol=l
hidt=dt
End
End
End
If ol>'' Then
Call o ol
Else
Say 'no matching item found'
End
When command='all' Then Do
Call lineout mydb
Parse Var text category
Do While lines(mydb)>0
l=linein(mydb)
Parse Var l a (x05) b
If category=''|,
category='-' & b=''|,
b=category Then
Call o l
End
End
When command='end' Then
Leave
Otherwise Do
Say 'invalid command ('command')'
Call help
End
End
End
Say 'Bye'
Exit
 
o: Parse Value arg(1) With dt text
Say left(dt,8) text
Return
 
help:
Say 'add item[,[category][,date]] to add an item'
Say 'latest category to list the latest item of a category'
Say 'latest to list the latest item'
Say 'all category to list all items of a category'
Say 'all to list all items'
Say 'end to end this program'
Say 'Use category - to list items without category'
Return</syntaxhighlight>
{{out}}
<pre> Enter your commands, ?, or end
?
add item[,[category][,date]] to add an item
latest category to list the latest item of a category
latest to list the latest item
all category to list all items of a category
all to list all items
end to end this program
Use category - to list items without category
add item1
adding item item1/ dated 20141006
add item2
adding item item2/ dated 20141006
add item3,cat3
adding item item3/cat3 dated 20141006
add item4,cat3,20201910
adding item item4/cat3 dated 20201910
add item5,cat3,190201910
adding item item5/cat3 dated 190201910
all
20141006 item1 �
20141006 item2 �
20141006 item3 � cat3
20201910 item4 � cat3
190201910 item5 � cat3
latest
20201910 item4 � cat3
latest cat1
no matching item found
latest cat3
20201910 item4 � cat3
end
Bye</pre>
 
=={{header|Ruby}}==
<langsyntaxhighlight lang="ruby">require 'date'
require 'json'
require 'securerandom'
Line 1,397 ⟶ 4,732:
end
 
process_command_line *ARGV</langsyntaxhighlight>
 
Sample session
Line 1,474 ⟶ 4,809:
{"fields":["event_title","start_time","stop_time","location","event_description"],"items":{"6dd02195-1efe-40d1-b43e-c2efd852cd1d":{"event_title":"Wife's Birthday","start_time":"2011-11-01","stop_time":"2011-11-01","location":"","event_description":"happy 39th"},"0190b835-401d-42da-9ed3-1d335d27b83c":{"event_title":"Parent-Teacher Conference","start_time":"2011-11-03 19:30","stop_time":"2011-11-03 20:00","location":"school","event_description":"desc"},"4023e6f1-bcc1-49e5-a59f-138157b413f4":{"event_title":"Buy gift for wife","start_time":"2011-10-31 16:00","stop_time":"2011-10-31 16:30","location":"the mall","event_description":"hmm, maybe jewelery?"}},"history":[[1320349951.000625,"6dd02195-1efe-40d1-b43e-c2efd852cd1d"],[1320350045.4736252,"0190b835-401d-42da-9ed3-1d335d27b83c"],[1320350102.9486248,"4023e6f1-bcc1-49e5-a59f-138157b413f4"]],"tags":{"birthday":["6dd02195-1efe-40d1-b43e-c2efd852cd1d"],"family":["6dd02195-1efe-40d1-b43e-c2efd852cd1d","0190b835-401d-42da-9ed3-1d335d27b83c","4023e6f1-bcc1-49e5-a59f-138157b413f4"],"school":["0190b835-401d-42da-9ed3-1d335d27b83c"],"last-minute":["4023e6f1-bcc1-49e5-a59f-138157b413f4"]}}
</pre>
=={{header|Run BASIC}}==
<lang runbasic>sqliteconnect #sql, "f:\client.db" ' Connect to the DB
 
=={{header|Scala}}==
' -------------------------------
<syntaxhighlight lang="scala">object SimpleDatabase extends App {
' show user options
type Entry = Array[String]
' -------------------------------
def asTSV(e: Entry) = e mkString "\t"
[sho]
def fromTSV(s: String) = s split "\t"
cls ' clear screen
val header = asTSV(Array("TIMESTAMP", "DESCRIPTION", "CATEGORY", "OTHER"))
button #acd, "Add a new entry", [add]
button #acd, "Print the latest entry", [last]
button #acd, "Print the latest entry for each category", [lastCat]
button #acd, "Print all entries sorted by a date", [date]
button #ex, "Exit", [exit]
wait
 
def read(filename: String) = try {
' ------------------------------------
scala.io.Source.fromFile(filename).getLines.drop(1).map(fromTSV)
' add a new entry
} catch {
' ------------------------------------
case e: java.io.FileNotFoundException => Nil
[add]
}
cls ' clear the screen
html "<TABLE BORDER=1 CELLPADDING=0 CELLSPACING=0 bgcolor=wheat>"
html "<TR align=center BGCOLOR=tan><TD colspan=2>Client Maintenance</TD></TR><TR>"
html "<TD bgcolor=tan align=right>Client Num</TD><TD>"
textbox #clientNum,clientNum$,5
 
def write(filename: String, all: Seq[Entry]) = {
html "</TD></TR><TR><TD bgcolor=tan align=right>Name</TD><TD>"
import java.nio.file.{Files,Paths}
textbox #name,name$,30
import scala.collection.JavaConversions.asJavaIterable
Files.write(Paths.get(filename), asJavaIterable(header +: all.map(asTSV)))
all.size
}
 
def add(filename: String, description: String, category: String = "none", optional: Seq[String] = Nil) {
html "</TD></TR><TR><TD bgcolor=tan align=right>Client Date</TD><TD>"
val format = new java.text.SimpleDateFormat("yyyy-MM-dd HH:mm:ss")
textbox #clientDate,clientDate$,19
val e = Array(format.format(new java.util.Date), description, category) ++ optional
println(write(filename, read(filename).toBuffer :+ e) + " entries")
}
 
def print(filename: String, filter: Seq[Entry] => TraversableOnce[Entry]) =
html "</TD></TR><TR><TD bgcolor=tan align=right>Category</TD><TD>"
filter(read(filename).toList.sortBy(_.headOption)) map(_ mkString ",") foreach println
textbox #category,category$,10
 
args match {
html "</TD></TR><TR><TR bgcolor=tan><TD colspan=2 ALIGN=CENTER>"
case Array(f, "latest") => print(f, _ takeRight 1)
button #acd, "Add", [addIt]
case Array(f, "latest", cat) => print(f, _ filter(_.lift(2) == Some(cat)) takeRight 1)
button #ex, "Exit", [sho]
case Array(f, "all") => print(f, _.toSeq)
html "</TD></TR></TABLE>"
case Array(f, "all", "latest") => print(f, _ groupBy (_ lift 2 getOrElse "") map{case (_, cat) => cat.last})
wait
case Array(f, "add", desc) => add(f, desc, category = "")
case Array(f, "add", desc, cat, opt @ _*) => add(f, desc, cat, opt)
case _ => println("Usage: SimpleDatabase filename.tsv [all [latest]| latest [CATEGORY] | add [DESCRIPTION [CATEGORY [OPTIONAL]...]]]")
}
}</syntaxhighlight>
{{out}}
<pre>> SimpleDatabase
Usage: SimpleDatabase filename.tsv [all [latest]| latest [CATEGORY] | add [DESCRIPTION [CATEGORY [OPTIONAL]...]]]
 
> SimpleDatabase database.tsv all
' ---------------------------------------------
' Get data from the screen
' ---------------------------------------------
[addIt]
clientNum = #clientNum contents$()
name$ = trim$(#name contents$())
clientDate$ = trim$(#clientDate contents$())
category$ = trim$(#category contents$())
dbVals$ = clientNum;",'";name$;"','";clientDate$;"','";category$;"'"
sql$ = "INSERT into client ("; dbFields$; ") VALUES ("; dbVals$ ; ")"
#sql execute(sql$)
goto [sho]
 
> SimpleDatabase database.tsv add one
1 entries
 
> SimpleDatabase database.tsv add two test
' ------------------------------------
2 entries
' Select last entry
' ------------------------------------
[last]
sql$ = "SELECT *,client.rowid as rowid FROM client ORDER BY rowid desc LIMIT 1"
what$ = "---- Last Entry ----"
goto [shoQuery]
 
> SimpleDatabase database.tsv add three test optional
' ------------------------------------
3 entries
' Select by category
' ------------------------------------
[lastCat]
sql$ = "SELECT *,client.rowid FROM client
WHERE client.rowid = (SELECT max(c.rowid)
FROM client as c WHERE c.category = client.category)
ORDER BY category"
what$ = "---- Last Category Sequence ----"
goto [shoQuery]
 
> SimpleDatabase database.tsv add four final
' ------------------------------------
4 entries
' Select by date
' ------------------------------------
[date]
sql$ = "SELECT * FROM client ORDER BY clientDate"
what$ = "---- By Date ----"
 
> SimpleDatabase database.tsv all
[shoQuery]
2014-10-03 12:00:01,one
cls
2014-10-03 12:00:02,two,test
print what$
2014-10-03 12:00:03,three,test,optional
html "<TABLE BORDER=1 CELLPADDING=0 CELLSPACING=0>"
2014-10-03 12:00:04,four,final
html "<TR align=center>"
html "<TD>Client<br>Num</TD>"
html "<TD>Name</TD>"
html "<TD>Client<br>Date</TD>"
html "<TD>Category</TD>"
html "</TR>"
#sql execute(sql$)
WHILE #sql hasanswer()
#row = #sql #nextrow()
clientNum = #row clientNum()
name$ = #row name$()
clientDate$ = #row clientDate$()
category$ = #row category$()
 
> SimpleDatabase database.tsv all latest
html "</TD>"
2014-10-03 12:00:04,four,final
html "<TD align=right>";clientNum;"</TD>"
2014-10-03 12:00:03,three,test,optional
html "<TD>";name$;"</TD>"
2014-10-03 12:00:01,one
html "<TD>";clientDate$;"</TD>"
html "<TD>";category$;"</TD>"
html "</TR>"
WEND
html "</TABLE>"
button #c, "Continue", [sho]
wait
 
> SimpleDatabase database.tsv latest
' ------ the end -------
2014-10-03 12:00:04,four,final
[exit]
end</lang>
Output:
 
> SimpleDatabase database.tsv latest test
---- User Input ----<br />
2014-10-03 12:00:03,three,test,optional</pre>
<TABLE BORDER=1 CELLPADDING=0 CELLSPACING=0 bgcolor=wheat>
<TR align=center BGCOLOR=tan><TD colspan=2>Client Maintenance</TD></TR>
<TR><TD bgcolor=tan align=right>Client Num</TD><TD>5</TD></TR>
<TR><TD bgcolor=tan align=right>Name</TD><TD>Dawnridge Winery</TD></TR>
<TR><TD bgcolor=tan align=right>Client Date</TD><TD><2008-06-18 22;16</TD></TR>
<TR><TD bgcolor=tan align=right>Category</TD><TD>wine></TD></TR>
<TR><TR bgcolor=tan><TD colspan=2 ALIGN=CENTER>[Add] [Exit]</TD></TR></TABLE>
 
---- Last Entry ----<br />
<TABLE BORDER=1 CELLPADDING=0 CELLSPACING=0>
<TR align=center><TD>Client<br>Num</TD><TD>Name</TD><TD>Client<br>Date</TD><TD>Category</TD></TR>
<TR><TD align=right>5</TD><TD>Dawnridge Winery</TD><TD>2008-06-18 22;16</TD><TD>wine</TD></TR></TABLE>
 
---- Last category Sequence ----<br />
<TABLE BORDER=1 CELLPADDING=0 CELLSPACING=0>
<TR align=center><TD>Client<br>Num</TD><TD>Name</TD><TD>Client<br>Date</TD><TD>Category</TD></TR>
<TR><TD align=right>1</TD><TD>Home Sales</TD><TD>2012-01-01 10;20</TD><TD>broker</TD></TR>
<TR><TD align=right>4</TD><TD>Back 40 Equipment</TD><TD>2009-09-18 20:18</TD><TD>farm</TD></TR>
<TR><TD align=right>3</TD><TD>Floral Designs</TD><TD>2010-10-14 09:16</TD><TD>flowers</TD></TR>
<TR><TD align=right>2</TD><TD>Best Foods</TD><TD>2011-02-02 12;33</TD><TD>food</TD></TR>
<TR><TD align=right>5</TD><TD>Dawnridge Winery</TD><TD>2008-06-18 22;16</TD><TD>wine</TD></TR></TABLE>
 
---- Date Sequence ----<br />
<TABLE BORDER=1 CELLPADDING=0 CELLSPACING=0>
<TR align=center><TD>Client<br>Num</TD><TD>Name</TD><TD>Client<br>Date</TD><TD>Category</TD></TR>
<TR><TD align=right>5</TD><TD>Dawnridge Winery</TD><TD>2008-06-18 22;16</TD><TD>wine</TD></TR>
<TR><TD align=right>4</TD><TD>Back 40 Equipment</TD><TD>2009-09-18 20:18</TD><TD>farm</TD></TR>
<TR><TD align=right>3</TD><TD>Floral Designs</TD><TD>2010-10-14 09:16</TD><TD>flowers</TD></TR>
<TR><TD align=right>2</TD><TD>Best Foods</TD><TD>2011-02-02 12;33</TD><TD>food</TD></TR>
<TR><TD align=right>1</TD><TD>Home Sales</TD><TD>2012-01-01 10;20</TD><TD>broker</TD></TR></TABLE>
 
=={{header|Tcl}}==
The format used is that of a Tcl dictionary, where each entry uses the title as a key and the remaining information (category, date and miscellaneous metadata) is the value associated with it. The only variation from the standard internal format is that entries are separated by newlines instead of spaces; this is still a legal value, but is a non-canonical.
<langsyntaxhighlight lang="tcl">#!/usr/bin/env tclsh8.6
package require Tcl 8.6
namespace eval udb {
Line 1,722 ⟶ 4,986:
}
 
udb::Store [lindex $argv 0]</langsyntaxhighlight>
Sample session:
<langsyntaxhighlight lang="bash">bash$ udb.tcl db
wrong # args: should be "udb.tcl dbfile subcommand ?args...?"
bash$ udb.tcl db ?
Line 1,814 ⟶ 5,078:
Title: Title 3
Category: bar
Date: Tue Nov 15 18:12:07 GMT 2011</langsyntaxhighlight>
 
=={{header|ToffeeScript}}==
<syntaxhighlight lang="coffeescript">#!/usr/local/bin/toffee
 
prog = require 'commander'
fs = require 'fs-extra'
 
if not fs.exists! 'data.json'
fs.outputJson! 'data.json', {}
 
prog
.command('add <name> <category> [date]')
.description('Add a new entry')
.option('-n <text>', 'notes')
.option('-t <tags>', 'tags')
.action addentry
 
prog
.command('latest')
.description('Print the latest entry')
.action latest
 
prog
.command('catlatest')
.description('Print the latest entry for each category')
.action catlatestout
 
prog
.command('list')
.description('Print all entries sorted by date')
.action bydate
 
 
addentry = (name, category, dt, options) ->
if dt? then dat = new Date(dt) else dat = new Date()
update =
name: name
category: category
tags: options?.T
notes: options?.N
date: dat.getTime()
e, data = fs.readJson! 'data.json'
if not data[category]?
data[category] = []
data[category].push update
fs.outputJson 'data.json', data
 
byDateNew = (a, b) ->
if a.date<b.date then return 1
if b.date>a.date then return -1
return 0
 
catlatest = (cb) ->
e, data = fs.readJson! 'data.json'
ret = []
for cat, list of data
list.sort byDateNew
ret.push list[0]
cb ret
 
printFormatted = (entry) ->
tmp = entry.date
entry.date = new Date(entry.date).toDateString()
console.log entry
entry.date = tmp
 
latest = ->
newpercat = catlatest!
newpercat.sort byDateNew
printFormatted newpercat[0]
 
catlatestout = ->
items = catlatest!
for item in items
printFormatted item
 
bydate = ->
e, data = fs.readJson! 'data.json'
entries = []
for cat, list of data
for item in list
entries.push item
entries.sort byDateNew
for entry in entries
printFormatted entry
 
prog.parse process.argv</syntaxhighlight>
 
=={{header|UNIX Shell}}==
This format is guaranteed to be human readable: if you can type it, you can read it.
<langsyntaxhighlight lang="bash">#!/bin/sh
 
db_create() {
Line 1,913 ⟶ 5,264:
show_help
;;
esac</langsyntaxhighlight>
Sample usage (assuming script is named "sdb"):<syntaxhighlight lang="text">$ sdb create CDs
Create DB `CDs'
$ sdb add CDs Bookends
Line 1,950 ⟶ 5,301:
$ sdb drop CDs
Delete DB `CDs'
$</langsyntaxhighlight>
 
=={{header|Wren}}==
{{trans|Kotlin}}
===Version 1===
{{libheader|Wren-ioutil}}
{{libheader|Wren-trait}}
{{libheader|Wren-iterate}}
{{libheader|Wren-date}}
{{libheader|Wren-sort}}
{{libheader|Wren-str}}
Note that since Wren CLI currently has no way of determining the current date/time, a date needs to be input for each item to be added.
<syntaxhighlight lang="wren">/* Simple_database.wren */
 
import "os" for Process
import "./ioutil" for File, FileFlags, FileUtil
import "./trait" for Comparable
import "./iterate" for Reversed
import "./date" for Date
import "./sort" for Sort
import "./str" for Str
 
var fileName = "Simple_database.csv"
 
Date.default = Date.isoDate
 
class Item is Comparable {
construct new(name, date, category) {
_name = name
_date = date
_category = category
}
 
name { _name }
date { _date }
category { _category }
 
compare(other) { _date.compare(other.date) }
 
toString { "%(name), %(date.toString), %(category)" }
}
 
var printUsage = Fn.new {
System.print("""
Usage:
wren Simple_database.wren cmd [categoryName]
add add item name and date, followed by optional category
latest print item with latest date, followed by optional category
all print all
For instance: add "some item name", "some item date", "some category name"
Dates should be in format: yyyy-mm-dd
""")
}
 
var load = Fn.new {
var db = []
var lines = FileUtil.readLines(fileName)
for (line in lines) {
if (line == "") break // end of file
var item = line.split(", ")
db.add(Item.new(item[0], Date.parse(item[1]), item[2]))
}
return db
}
 
var store = Fn.new { |item|
File.openWithFlags(fileName, FileFlags.writeOnly) { |f|
f.writeBytes("%(item)\n")
}
}
 
var addItem = Fn.new { |input|
if (input.count < 2) {
printUsage.call()
return
}
var date = Date.parse(input[1])
var cat = (input.count == 3) ? input[2] : "none"
store.call(Item.new(input[0], date, cat))
}
 
var printLatest = Fn.new { |a|
var db = load.call()
if (db.isEmpty) {
System.print("No entries in database.")
return
}
Sort.quick(db) // sort by ascending date
if (a.count == 1) {
var found = false
for (item in Reversed.new(db)) {
if (item.category == a[0]) {
System.print(item)
found = true
break
}
}
if (!found) System.print("There are no items for category '%(a[0])'.")
} else System.print(db[-1])
}
 
var printAll = Fn.new {
var db = load.call()
if (db.isEmpty) {
System.print("No entries in database.")
return
}
Sort.quick(db) // sort by ascending date
for (item in db) System.print(item)
}
 
var args = Process.arguments
if (!(1..4).contains(args.count)) {
printUsage.call()
return
}
// create file if it doesn't already exist
if (!File.exists(fileName)) {
var f = File.create(fileName)
f.close()
}
 
var cmd = Str.lower(args[0])
if (cmd == "add") {
addItem.call(args[1..-1])
} else if (cmd == "latest") {
printLatest.call(args[1..-1])
} else if (cmd == "all") {
printAll.call()
} else {
printUsage.call()
}</syntaxhighlight>
 
{{out}}
Sample session:
<pre>
$ wren Simple_database.wren add item1 2021-03-01
$ wren Simple_database.wren add item2 2021-04-01
$ wren Simple_database.wren add item3 2021-05-01 cat3
$ wren Simple_database.wren add item4 2021-06-01 cat3
$ wren Simple_database.wren add item5 2021-07-01 cat3
$ wren Simple_database.wren latest
item5, 2021-07-01, cat3
$ wren Simple_database.wren latest none
item2, 2021-04-01, none
$ wren Simple_database.wren latest cat4
There are no items for category 'cat4'.
$ wren Simple_database.wren all
item1, 2021-03-01, none
item2, 2021-04-01, none
item3, 2021-05-01, cat3
item4, 2021-06-01, cat3
item5, 2021-07-01, cat3
</pre>
<br>
===Version 2===
{{libheader|Wren-table}}
The above module provides a more generic way to create simple databases and was not available when the first version was written.
<syntaxhighlight lang="wren">import "os" for Process
import "./table" for Table, FieldInfo, File
import "./str" for Str
 
var printUsage = Fn.new {
System.print("""
Usage:
wren Simple_database.wren cmd [categoryName]
add add item name and date, followed by optional category
latest print item with latest date, followed by optional category
all print all
For instance: add "some item name", "some item date", "some category name"
Dates should be in format: yyyy-mm-dd
""")
}
 
var printLatest = Fn.new { |table, a|
if (table.isEmpty) {
System.print("No entries in table.")
return
}
var records = table.records
records.sort { |s, t| Str.lt(s[1], t[1]) } // sort by ascending date
if (a.count == 1) {
var found = false
for (record in records[-1..0]) {
if (record[2] == a[0]) {
System.print(record)
found = true
break
}
}
if (!found) System.print("There are no records for category '%(a[0])'.")
} else System.print(records[-1])
}
 
var args = Process.arguments
if (!(1..4).contains(args.count)) {
printUsage.call()
return
}
 
// create a new Table object
var tableName = "Simple_database"
var table
if (Table.fileExists(tableName)) {
table = Table.load(tableName)
} else {
var fis = [
FieldInfo.new("name", String),
FieldInfo.new("date", String),
FieldInfo.new("category", String)
]
table = Table.new(tableName, fis)
}
 
var cmd = Str.lower(args[0])
if (cmd == "add") {
if (args.count < 4) args.add("none")
table.add(args[1..-1])
table.save()
} else if (cmd == "latest") {
printLatest.call(table, args[1..-1])
} else if (cmd == "all") {
table.list()
} else {
printUsage.call()
}</syntaxhighlight>
 
{{out}}
<pre>
$ wren Simple_database.wren add item1 2021-03-01
$ wren Simple_database.wren add item2 2021-04-01
$ wren Simple_database.wren add item3 2021-05-01 cat3
$ wren Simple_database.wren add item4 2021-06-01 cat3
$ wren Simple_database.wren add item5 2021-07-01 cat3
$ wren Simple_database.wren latest
[item5, 2021-07-01, cat3]
$ wren Simple_database.wren latest none
[item2, 2021-04-01, none]
$ wren Simple_database.wren latest cat4
There are no records for category 'cat4'.
$ wren Simple_database.wren all
Records in 'Simple_database' table:
 
name date category
----- ---------- --------
item1 2021-03-01 none
item2 2021-04-01 none
item3 2021-05-01 cat3
item4 2021-06-01 cat3
item5 2021-07-01 cat3
</pre>
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