Parameterized SQL statement
You are encouraged to solve this task according to the task description, using any language you may know.
Parameterized SQL statements are an easy way to avoid SQL injection attacks. SQL drivers and libraries will automatically "sanitize" input to parameterized SQL statements to avoid these catastrophic database attacks. Second, parameterized SQL performs better. A lot better.
Using a SQL update statement like this one (spacing is optional):
UPDATE players
SET name = 'Smith, Steve', score = 42, active = true
WHERE jerseyNum = 99
show how to make a parameterized SQL statement, set the parameters to the values given above, and execute the statement.
Non-parameterized SQL is the GoTo statement of database programming. Don't do it, and make sure your coworkers don't either.
8th
\ assuming the var 'db' contains an opened database with a schema matching the problem:
db @
"UPDATE players SET name=?1,score=?2,active=?3 WHERE jerseyNum=?4"
db:prepare var, stmt
\ bind values to the statement:
stmt @ 1 "Smith, Steve" db:bind
2 42 db:bind
3 true db:bind
4 99 db:bind
\ execute the query
db @ swap db:exec
Ada
-- Version for sqlite
with GNATCOLL.SQL_Impl; use GNATCOLL.SQL_Impl;
with GNATCOLL.SQL.Exec; use GNATCOLL.SQL.Exec;
with GNATCOLL.SQL.Sqlite; use GNATCOLL.SQL;
procedure Prepared_Query is
DB_Descr : Database_Description;
Conn : Database_Connection;
Query : Prepared_Statement;
--sqlite does not support boolean fields
True_Str : aliased String := "TRUE";
Param : SQL_Parameters (1 .. 4) :=
(1 => (Parameter_Text, null),
2 => (Parameter_Integer, 0),
3 => (Parameter_Text, null),
4 => (Parameter_Integer, 0));
begin
-- Allocate and initialize the description of the connection
Setup_Database (DB_Descr, "rosetta.db", "", "", "", DBMS_Sqlite);
-- Allocate the connection
Conn := Sqlite.Build_Sqlite_Connection (DB_Descr);
-- Initialize the connection
Reset_Connection (DB_Descr, Conn);
Query :=
Prepare
("UPDATE players SET name = ?, score = ?, active = ? " &
" WHERE jerseyNum = ?");
declare
Name : aliased String := "Smith, Steve";
begin
Param := ("+" (Name'Access), "+" (42), "+" (True_Str'Access), "+" (99));
Execute (Conn, Query, Param);
end;
Commit_Or_Rollback (Conn);
Free (Conn);
Free (DB_Descr);
end Prepared_Query;
Arturo
; Helper functions
createTable: function [][
query db {!sql DROP TABLE IF EXISTS users}
query db {!sql
CREATE TABLE users (
ID INTEGER PRIMARY KEY AUTOINCREMENT,
username TEXT NOT NULL,
email TEXT NOT NULL,
age INTEGER
)
}
]
addUser: function [name, email, age][
query.id db .with:@[name,email,age] {!sql
INSERT INTO users (username, email, age)
VALUES (?,?,?)
}
]
findUser: function [name][
query db .with:@[name] ~{!sql
SELECT *
FROM users
WHERE username=?
}
]
db: open.sqlite "users.db"
createTable
print ["added user with id:" addUser "JohnDoe" "jodoe@gmail.com" 35]
print ["added user with id:" addUser "JaneDoe" "jadoe@gmail.com" 14]
print ["getting user with name: JohnDoe =>" findUser "JohnDoe"]
close db
- Output:
added user with id: 1 added user with id: 2 getting user with name: JohnDoe => [[1 JohnDoe jodoe@gmail.com 35]]
BASIC
BASIC256
# open database file
dbopen "players.sqlite3"
# delete old players table - trap error if new database
onerror errortrap
# delete old database if it exists
dbexecute "DROP TABLE IF EXISTS players;"
# create database table with sample data
# include the IF NOT EXISTS clause to avoid an error if the table already exists.
dbexecute "CREATE TABLE IF NOT EXISTS players (name TEXT NOT NULL, score INTEGER, active BIT, jerseyNum INTEGER);"
dbexecute "INSERT INTO players VALUES ('Jones, Bob',0,'N',99)"
dbexecute "INSERT INTO players VALUES ('Jesten, Jim',0,'N',100)"
dbexecute "INSERT INTO players VALUES ('Jello, Frank',0,'N',101)"
dbexecute "UPDATE players SET name = 'Smith, Steve', score = 42, active = 'TRUE' WHERE jerseyNum = 99;"
dbopenset "SELECT * FROM players;"
while dbrow()
print "['" + dbstring(0) + ", '" + dbstring(1) + ", '" + dbstring(2) + "', " + dbstring(3) + "]"
end while
dbcloseset
offerror
# wrap everything up
dbclose
end
errortrap:
# accept error - display nothing - return to next statement
return
- Output:
Same as PureBasic entry.
FreeBASIC
#include once "sqlite3.bi"
#define NULL 0
Dim As sqlite3 Ptr db
Dim As sqlite3_stmt Ptr stmt
Dim As Integer rc
' Open database file
rc = sqlite3_open("players.sqlite3", @db)
If rc <> SQLITE_OK Then
Print "No se puede abrir la base de datos: "; *sqlite3_errmsg(db)
sqlite3_close(db)
End 1
End If
' Delete old database if it exists
sqlite3_exec(db, "DROP TABLE IF EXISTS players;", NULL, NULL, NULL)
' Create database table with sample data
sqlite3_exec(db, "CREATE TABLE IF NOT EXISTS players (name TEXT NOT NULL, score INTEGER, active BIT, jerseyNum INTEGER);", NULL, NULL, NULL)
sqlite3_exec(db, "INSERT INTO players VALUES ('Jones, Bob',0,'N',99)", NULL, NULL, NULL)
sqlite3_exec(db, "INSERT INTO players VALUES ('Jesten, Jim',0,'N',100)", NULL, NULL, NULL)
sqlite3_exec(db, "INSERT INTO players VALUES ('Jello, Frank',0,'N',101)", NULL, NULL, NULL)
' Update name and score of player with jersey number 99
sqlite3_exec(db, "UPDATE players SET name = 'Smith, Steve', score = 42, active = 'TRUE' WHERE jerseyNum = 99;", NULL, NULL, NULL)
' Query and display all player table records
Dim As sqlite3_stmt Ptr stmt2
Dim As String query3 = "SELECT * FROM players"
rc = sqlite3_prepare_v2(db, Strptr(query3), -1, @stmt2, 0)
While sqlite3_step(stmt2) = SQLITE_ROW
Print "['"; *Cptr(ZString Ptr, sqlite3_column_text(stmt2, 0)); "', ";
Print *Cptr(ZString Ptr, sqlite3_column_text(stmt2, 1)); ", ";
Print *Cptr(ZString Ptr, sqlite3_column_text(stmt2, 2)); ", ";
Print sqlite3_column_int(stmt2, 3); "]"
Wend
' Close the database
sqlite3_finalize(stmt2)
sqlite3_close(db)
Sleep
- Output:
Same as PureBasic entry.
PureBasic
UseSQLiteDatabase()
Procedure CheckDatabaseUpdate(database, query$)
result = DatabaseUpdate(database, query$)
If result = 0
PrintN(DatabaseError())
EndIf
ProcedureReturn result
EndProcedure
If OpenConsole()
If OpenDatabase(0, ":memory:", "", "")
;create players table with sample data
CheckDatabaseUpdate(0, "CREATE table players (name, score, active, jerseyNum)")
CheckDatabaseUpdate(0, "INSERT INTO players VALUES ('Jones, Bob',0,'N',99)")
CheckDatabaseUpdate(0, "INSERT INTO players VALUES ('Jesten, Jim',0,'N',100)")
CheckDatabaseUpdate(0, "INSERT INTO players VALUES ('Jello, Frank',0,'N',101)")
Define name$, score, active$, jerseynum
name$ = "Smith, Steve"
score = 42
active$ ="TRUE"
jerseynum = 99
SetDatabaseString(0, 0, name$)
SetDatabaseLong(0, 1, score)
SetDatabaseString(0, 2, active$)
SetDatabaseLong(0, 3, jerseynum)
CheckDatabaseUpdate(0, "UPDATE players SET name = ?, score = ?, active = ? WHERE jerseyNum = ?")
;display database contents
If DatabaseQuery(0, "Select * from players")
While NextDatabaseRow(0)
name$ = GetDatabaseString(0, 0)
score = GetDatabaseLong(0, 1)
active$ = GetDatabaseString(0, 2)
jerseynum = GetDatabaseLong(0, 3)
row$ = "['" + name$ + "', " + score + ", '" + active$ + "', " + jerseynum + "]"
PrintN(row$)
Wend
FinishDatabaseQuery(0)
EndIf
CloseDatabase(0)
Else
PrintN("Can't open database !")
EndIf
Print(#CRLF$ + #CRLF$ + "Press ENTER to exit"): Input()
CloseConsole()
EndIf
Sample output:
['Smith, Steve', 42, 'TRUE', 99] ['Jesten, Jim', 0, 'N', 100] ['Jello, Frank', 0, 'N', 101]
Run BASIC
sqliteconnect #mem, ":memory:"
#mem execute("CREATE table players (name, score, active, jerseyNum)")
#mem execute("INSERT INTO players VALUES ('Jones, Bob',0,'N',99)")
#mem execute("INSERT INTO players VALUES ('Jesten, Jim',0,'N',100)")
#mem execute("INSERT INTO players VALUES ('Jello, Frank',0,'N',101)")
sql$ = "
UPDATE players
SET name = 'Smith, Steve',
score = 42,
active = 'TRUE'
WHERE jerseyNum = 99"
#mem execute(sql$)
#mem execute("SELECT * FROM players ORDER BY jerseyNum")
WHILE #mem hasanswer()
#row = #mem #nextrow()
name$ = #row name$()
score = #row score()
active$ = #row active$()
jerseyNum = #row jerseyNum()
print name$;chr$(9);score;chr$(9);active$;chr$(9);jerseyNum
WEND
end
Output Smith, Steve 42 TRUE 99 Jesten, Jim 0 N 100 Jello, Frank 0 N 101
C
Compile with:
gcc example.c -lsqlite3
Tested with gcc version 4.9.2 (Raspbian 4.9.2-10) and SQLite 3.8.7.1
#include <stdio.h>
#include <stdlib.h>
#include <sqlite3.h>
static const char* db_file = ":memory:"; // Create an in-memory database.
void check_error(int result_code, sqlite3 *db);
int select_callback(void* data, int column_count, char** columns, char** column_names);
int main(void) {
sqlite3 *db;
int result_code;
char *sql;
char *insert_statements[4];
sqlite3_stmt *compiled_statement;
int i;
// Open the database.
result_code = sqlite3_open(db_file, &db);
check_error(result_code, db);
// Create the players table in the database.
sql = "create table players("
"id integer primary key asc, "
"name text, "
"score real, "
"active integer, " // Store the bool value as integer (see https://sqlite.org/datatype3.html chapter 2.1).
"jerseyNum integer);";
result_code = sqlite3_exec(db, sql, NULL, NULL, NULL);
check_error(result_code, db);
// Insert some values into the players table.
insert_statements[0] = "insert into players (name, score, active, jerseyNum) "
"values ('Roethlisberger, Ben', 94.1, 1, 7);";
insert_statements[1] = "insert into players (name, score, active, jerseyNum) "
"values ('Smith, Alex', 85.3, 1, 11);";
insert_statements[2] = "insert into players (name, score, active, jerseyNum) "
"values ('Manning, Payton', 96.5, 0, 18);";
insert_statements[3] = "insert into players (name, score, active, jerseyNum) "
"values ('Doe, John', 15, 0, 99);";
for (i=0; i<4; i++) {
result_code = sqlite3_exec(db, insert_statements[i], NULL, NULL, NULL);
check_error(result_code, db);
}
// Display the contents of the players table.
printf("Before update:\n");
sql = "select * from players;";
result_code = sqlite3_exec(db, sql, select_callback, NULL, NULL);
check_error(result_code, db);
// Prepare the parametrized SQL statement to update player #99.
sql = "update players set name=?, score=?, active=? where jerseyNum=?;";
result_code = sqlite3_prepare_v2(db, sql, -1, &compiled_statement, NULL);
check_error(result_code, db);
// Bind the values to the parameters (see https://sqlite.org/c3ref/bind_blob.html).
result_code = sqlite3_bind_text(compiled_statement, 1, "Smith, Steve", -1, NULL);
check_error(result_code, db);
result_code = sqlite3_bind_double(compiled_statement, 2, 42);
check_error(result_code, db);
result_code = sqlite3_bind_int(compiled_statement, 3, 1);
check_error(result_code, db);
result_code = sqlite3_bind_int(compiled_statement, 4, 99);
check_error(result_code, db);
// Evaluate the prepared SQL statement.
result_code = sqlite3_step(compiled_statement);
if (result_code != SQLITE_DONE) {
printf("Error #%d: %s\n", result_code, sqlite3_errmsg(db));
sqlite3_close(db);
return result_code;
}
// Destroy the prepared statement object.
result_code = sqlite3_finalize(compiled_statement);
check_error(result_code, db);
// Display the contents of the players table.
printf("After update:\n");
sql = "select * from players;";
result_code = sqlite3_exec(db, sql, select_callback, NULL, NULL);
check_error(result_code, db);
// Close the database connection.
sqlite3_close(db);
return EXIT_SUCCESS;
}
/*
Checks the result code from an SQLite operation.
If it contains an error code then this function prints the error message,
closes the database and exits.
*/
void check_error(int result_code, sqlite3 *db) {
if (result_code != SQLITE_OK) {
printf("Error #%d: %s\n", result_code, sqlite3_errmsg(db));
sqlite3_close(db);
exit(result_code);
}
}
/* This callback function prints the results of the select statement. */
int select_callback(void* data, int column_count, char** columns, char** column_names) {
int i;
for (i=0; i<column_count; i++) {
printf(columns[i]);
if (i < column_count-1) printf(" | ");
}
printf("\n");
}
- Output:
Before update: 1 | Roethlisberger, Ben | 94.1 | 1 | 7 2 | Smith, Alex | 85.3 | 1 | 11 3 | Manning, Payton | 96.5 | 0 | 18 4 | Doe, John | 15.0 | 0 | 99 After update: 1 | Roethlisberger, Ben | 94.1 | 1 | 7 2 | Smith, Alex | 85.3 | 1 | 11 3 | Manning, Payton | 96.5 | 0 | 18 4 | Smith, Steve | 42.0 | 1 | 99
C#
using System.Data.Sql;
using System.Data.SqlClient;
namespace ConsoleApplication1
{
class Program
{
static void Main(string[] args)
{
using var tConn = new SqlConnection("ConnectionString");
using var tCommand = tConn.CreateCommand();
tCommand.CommandText = "UPDATE players SET name = @name, score = @score, active = @active WHERE jerseyNum = @jerseyNum";
tCommand.Parameters.Add(new SqlParameter("@name", System.Data.SqlDbType.VarChar).Value = "Smith, Steve");
tCommand.Parameters.Add(new SqlParameter("@score", System.Data.SqlDbType.Int).Value = "42");
tCommand.Parameters.Add(new SqlParameter("@active", System.Data.SqlDbType.Bit).Value = true);
tCommand.Parameters.Add(new SqlParameter("@jerseyNum", System.Data.SqlDbType.Int).Value = "99");
tCommand.ExecuteNonQuery();
}
}
}
C++
This example uses the Qt SQL module to access an ODBC data source.
#include <QtSql>
#include <iostream>
// Command line arguments: data-source user password
// Obviously in a real application the password would be obtained in a secure manner.
int main(int argc, char *argv[]) {
if (argc != 4) {
std::cerr << "Usage: " << argv[0] << " data-source user password\n";
return 1;
}
QSqlDatabase db = QSqlDatabase::addDatabase("QODBC");
db.setDatabaseName(argv[1]);
if (!db.open(argv[2], argv[3])) {
auto error = db.lastError();
std::cerr << "Cannot connect to data source: " << error.text().toStdString() << '\n';
} else {
std::cout << "Connected to data source.\n";
QSqlQuery query(db);
query.prepare("UPDATE players SET name = ?, score = ?, active = ? WHERE jerseyNum = ?");
query.bindValue(0, "Smith, Steve");
query.bindValue(1, 42);
query.bindValue(2, true);
query.bindValue(3, 99);
if (!query.exec()) {
auto error = db.lastError();
std::cerr << "Cannot update database: " << error.text().toStdString() << '\n';
} else {
std::cout << "Update succeeded.\n";
}
}
return 0;
}
Clojure
(require '[clojure.java.jdbc :as sql])
; Using h2database for this simple example.
(def db {:classname "org.h2.Driver"
:subprotocol "h2:file"
:subname "db/my-dbname"})
(sql/update! db :players {:name "Smith, Steve" :score 42 :active true} ["jerseyNum = ?" 99])
; As an alternative to update!, use execute!
(sql/execute! db ["UPDATE players SET name = ?, score = ?, active = ? WHERE jerseyNum = ?" "Smith, Steve" 42 true 99])
DuckDB
A point of interest illustrated in the example below is that the parameter values presented when the "prepared" statement is executed are subject to automatic type casting: notice that the EXECUTE statement presents the fourth argument as a string but is cast to a UINTEGER.
# Setup
create or replace table players
(name VARCHAR, score INTEGER, active BOOLEAN, jerseyNum UINTEGER);
insert into players values (NULL, NULL, NULL, 99);
# Parameterized SQL
prepare update_players as
-- (name, score, active, jerseyNum)
UPDATE players
SET name = $1, score = $2, active = $3
WHERE jerseyNum = $4
;
execute update_players('Lynx', 10, true, '99');
from players;
- Output:
┌─────────┬───────┬─────────┬───────────┐ │ name │ score │ active │ jerseyNum │ │ varchar │ int32 │ boolean │ uint32 │ ├─────────┼───────┼─────────┼───────────┤ │ Lynx │ 10 │ true │ 99 │ └─────────┴───────┴─────────┴───────────┘
F#
open System.Data.SqlClient
[<EntryPoint>]
let main argv =
use tConn = new SqlConnection("ConnectionString")
use tCommand = new SqlCommand()
tCommand.Connection <- tConn
tCommand.CommandText <- "UPDATE players SET name = @name, score = @score, active = @active WHERE jerseyNum = @jerseyNum"
tCommand.Parameters.Add(SqlParameter("@name", System.Data.SqlDbType.VarChar).Value = box "Smith, Steve") |> ignore
tCommand.Parameters.Add(SqlParameter("@score", System.Data.SqlDbType.Int).Value = box 42) |> ignore
tCommand.Parameters.Add(SqlParameter("@active", System.Data.SqlDbType.Bit).Value = box true) |> ignore
tCommand.Parameters.Add(SqlParameter("@jerseyNum", System.Data.SqlDbType.Int).Value = box 99) |> ignore
tCommand.ExecuteNonQuery() |> ignore
0
Go
package main
import (
"database/sql"
"fmt"
_ "github.com/mattn/go-sqlite3"
)
func main() {
db, _ := sql.Open("sqlite3", "rc.db")
defer db.Close()
db.Exec(`create table players (name, score, active, jerseyNum)`)
db.Exec(`insert into players values ("",0,0,"99")`)
db.Exec(`insert into players values ("",0,0,"100")`)
// Parameterized
db.Exec(`update players set name=?, score=?, active=? where jerseyNum=?`,
"Smith, Steve", 42, true, "99")
rows, _ := db.Query("select * from players")
var (
name string
score int
active bool
jerseyNum string
)
for rows.Next() {
rows.Scan(&name, &score, &active, &jerseyNum)
fmt.Printf("%3s %12s %3d %t\n", jerseyNum, name, score, active)
}
rows.Close()
}
- Output:
99 Smith, Steve 42 true 100 0 false
Haskell
Example uses the HDBC package:
module Main (main) where
import Database.HDBC (IConnection, commit, run, toSql)
updatePlayers :: IConnection a => a -> String -> Int -> Bool -> Int -> IO Bool
updatePlayers conn name score active jerseyNum = do
rowCount <- run conn
"UPDATE players\
\ SET name = ?, score = ?, active = ?\
\ WHERE jerseyNum = ?"
[ toSql name
, toSql score
, toSql active
, toSql jerseyNum
]
commit conn
return $ rowCount == 1
main :: IO ()
main = undefined
You'll need an instance of a type with an instance for the IConnection type class in order to use this function, such as Connection from HDBC-postgresql.
Huginn
import Database as db;
import Algorithms as algo;
import FileSystem as fs;
main() {
dbPath = "/tmp/parametrized-sql.sqlite";
fs.remove( dbPath );
fs.open( dbPath, fs.OPEN_MODE.WRITE );
conn = db.connect( "sqlite3:///" + dbPath );
// Setup...
conn.query(
"CREATE TABLE Players (\n"
"\tname VARCHAR(64),\n"
"\tscore FLOAT,\n"
"\tactive INTEGER,\n"
"\tno VARCHAR(8)\n"
");"
).execute();
conn.query(
"INSERT INTO Players VALUES ( 'name', 0, 'false', 99 );"
).execute();
conn.query(
"INSERT INTO Players VALUES ( 'name', 0, 'false', 100 );"
).execute();
// Demonstrate parameterized SQL...
parametrizedQuery = conn.query(
"UPDATE Players SET name=?, score=?, active=? WHERE no=?"
);
for ( i, v : algo.enumerate( ( "Smith, Steve", 42, true, 99 ) ) ) {
parametrizedQuery.bind( i + 1, string( v ) );
}
parametrizedQuery.execute();
// and show the results...
for ( record : conn.query( "SELECT * FROM Players;" ).execute() ) {
print( "{}\n".format( record ) );
}
return ( 0 );
}
Java
import java.sql.DriverManager;
import java.sql.Connection;
import java.sql.PreparedStatement;
public class DBDemo{
private String protocol; //set this to some connection protocol like "jdbc:sqlserver://"
private String dbName; //set this to the name of your database
private String username;
private String password;
PreparedStatement query;
public int setUpAndExecPS(){
try {
Connection conn = DriverManager.getConnection(protocol + dbName, username, password);
query = conn.prepareStatement(
"UPDATE players SET name = ?, score = ?, active = ? WHERE jerseyNum = ?");
query.setString(1, "Smith, Steve");//automatically sanitizes and adds quotes
query.setInt(2, 42);
query.setBoolean(3, true);
query.setInt(4, 99);
//there are similar methods for other SQL types in PerparedStatement
return query.executeUpdate();//returns the number of rows changed
//PreparedStatement.executeQuery() will return a java.sql.ResultSet,
//execute() will simply return a boolean saying whether it succeeded or not
} catch (Exception e) {
e.printStackTrace();
}
return 0;
}
}
Julia
Uses the SQLite package.
using SQLite
name = "Smith, Steve"
jerseys = Dict("Smith, Steve" => 99)
sqlbool(tf::Bool) = if(tf) "TRUE" else "FALSE" end
db = SQLite.DB() # no filename given, so create an in-memory temporary
SQLite.execute!(db, "create table players (id integer primary key,
name text,
score number,
active bool,
jerseynum integer)")
SQLite.query(db, "INSERT INTO players (name, score, active, jerseynum) values ('Jones, James', 9, 'FALSE', 99)")
SQLite.query(db, "UPDATE players SET name = ?, score = ?, active = ? WHERE jerseynum = ?";
values = ["Smith, Steve", 42, sqlbool(true), jerseys[name]])
tbl = SQLite.query(db, "SELECT * from players")
println(tbl)
- Output:
1×5 DataFrames.DataFrame │ Row │ id │ name │ score │ active │ jerseynum │ ├─────┼────┼────────────────┼───────┼────────┼───────────┤ │ 1 │ 1 │ "Smith, Steve" │ 42 │ "TRUE" │ 99 │
Kotlin
// Version 1.2.41
import java.sql.DriverManager
import java.sql.Connection
fun main(args: Array<String>) {
val url = "jdbc:mysql://localhost:3306/test"
val username = "example"
val password = "password123"
val conn = DriverManager.getConnection(url, username, password)
val query = conn.prepareStatement(
"UPDATE players SET name = ?, score = ?, active = ? WHERE jerseyNum = ?"
)
with (query) {
setString(1, "Smith, Steve")
setInt(2, 42)
setBoolean(3, true)
setInt(4, 99)
val rowCount = executeUpdate()
if (rowCount == 0) println("Update failed")
close()
}
conn.close()
}
M2000 Interpreter
Module Parametrized_Sql {
Base "rosetta" ' warning erase database if found it in current directory
Execute "rosetta", {create table players (name VarChar(64), score Float, active Integer, jerseyNum Integer);}
Append "rosetta", "players","name",0,FALSE,99
sql$={
UPDATE players
SET name = '{0}', score = {1}, active = {2}
WHERE jerseyNum = {3}
}
Execute "rosetta", format$(sql$,"Smith, Steve", 42,TRUE, 99)
Retrieve "rosetta","players",1,"jerseyNum",99
Read how_many
Read Name$,score, active,jerseynum
Print Name$="Smith, Steve", score=42, active=True, jerseynum=99 ' true true true true
}
Parametrized_Sql
MariaDB
A one-off prepared statement:
BEGIN NOT ATOMIC
DECLARE customer_id TEXT DEFAULT 24;
EXECUTE IMMEDIATE 'SELECT * FROM customer WHERE id = ?' USING customer_id;
END;
A prepared statement used multiple times:
BEGIN NOT ATOMIC
DECLARE customer_1 TEXT DEFAULT 24;
DECLARE customer_2 TEXT DEFAULT 777;
PREPARE stmt FROM 'SELECT * FROM customer WHERE id = ?';
EXECUTE stmt USING customer_1;
EXECUTE stmt USING customer_2;
DEALLOCATE PREPARE stmt;
END;
Mathematica /Wolfram Language
Needs["DatabaseLink`"];
conn=OpenSQLConnection[JDBC["ODBC(DSN)","testdb"],"Username"->"John","Password"->"JohnsPassword"];
SQLExecute[conn,"UPDATE players SET name = `1`, score = `2`, active = `3` WHERE jerseyNum = `4`", {SQLArgument["Smith, Steve",42,True,99]}]
CloseSQLConnection[conn];
NetRexx
Using an Apache Derby embedded database:
/* NetRexx */
options replace format comments java crossref symbols nobinary
import java.sql.
-- =============================================================================
class RParameterizedSQLSimple public
properties indirect
connexion = Connection
properties inheritable constant
DRIVER = "org.apache.derby.jdbc.EmbeddedDriver"
DBURL = "jdbc:derby:"
DBNAME = "/workspace/DB.DerbySamples/DB/TEAMS01"
DBMODE_CREATE = ";create=true"
DBMODE_NOCREATE = ";create=false"
DBMODE_SHUTDOWN = ";shutdown=true"
-- =============================================================================
method RParameterizedSQLSimple()
setConnexion(null)
return
-- =============================================================================
method createConnexion() inheritable returns Connection signals ClassNotFoundException, InstantiationException, IllegalAccessException
if getConnexion() = null then do
props = Properties()
props.put("user", "user1")
props.put("password", "user1")
xURL = String DBURL || DBNAME || DBMODE_CREATE
loadDriver(DRIVER)
setConnexion(DriverManager.getConnection(xURL, props))
end
return getConnexion()
-- =============================================================================
method shutdownConnexion() inheritable returns boolean signals SQLException
dbState = boolean
xURL = String DBURL || DBNAME || DBMODE_SHUTDOWN
do
DriverManager.getConnection(xURL)
dbState = isTrue
catch se = SQLException
if (se.getErrorCode() = 50000) & ("XJ015".equals(se.getSQLState())) then do
say "Derby shut down normally"
dbState = isTrue
end
else if (se.getErrorCode() = 45000) & ("08006".equals(se.getSQLState())) then do
say "Derby database shut down normally"
dbState = isTrue
end
else do
say "Derby did not shut down normally"
dbState = isFalse
signal se
end
end
return dbState
-- =============================================================================
method loadDriver(xdriver = String) inheritable static signals ClassNotFoundException, InstantiationException, IllegalAccessException
do
Class.forName(xdriver).newInstance()
say "Loaded the appropriate driver"
catch cnfe = ClassNotFoundException
say "Unable to load the JDBC driver" xdriver
say "Please check your CLASSPATH."
signal cnfe
catch ie = InstantiationException
say "Unable to instantiate the JDBC driver" xdriver
signal ie
catch iae = IllegalAccessException
say "Not allowed to access the JDBC driver" xdriver
signal iae
end
return
-- =============================================================================
method updatePlayer(jerseyNum = int, name = String, score = int, active = boolean) binary inheritable returns int signals SQLException
updateSQL = "" -
|| "UPDATE TEAM.PLAYERS" -
|| " SET NAME = ?, SCORE = ?, ACTIVE = ?" -
|| " WHERE JERSEYNUM = ?"
rowCt = int
ix = int 0
ps = getConnexion().prepareStatement(updateSQL)
ix = ix + 1; ps.setString(ix, name)
ix = ix + 1; ps.setInt(ix, score)
ix = ix + 1; ps.setBoolean(ix, active)
ix = ix + 1; ps.setInt(ix, jerseyNum)
rowCt = ps.executeUpdate()
return rowCt
-- =============================================================================
method main(args = String[]) public static
do
tda = RParameterizedSQLSimple()
tda.createConnexion()
if tda.getConnexion() \= null then do
updated = tda.updatePlayer(99, "Smith, Steve", 42, isTrue)
if updated > 0 then say "Update successful"
else say "Update failed"
finally
tda.shutdownConnexion()
end
catch ex = Exception
ex.printStackTrace
end
return
-- =============================================================================
method isTrue() public static returns boolean
return 1 == 1
-- =============================================================================
method isFalse() public static returns boolean
return \isTrue
Nim
Using an SQLite in memory database and "db_sqlite" high level binding from standard library.
import db_sqlite
let db = open(":memory:", "", "", "")
# Setup
db.exec(sql"CREATE TABLE players (name, score, active, jerseyNum)")
db.exec(sql"INSERT INTO players VALUES (?, ?, ?, ?)", "name", 0, "false", 99)
# Update the row.
db.exec(sql"UPDATE players SET name=?, score=?, active=? WHERE jerseyNum=?",
"Smith, Steve", 42, true, 99)
# Display result.
for row in db.fastRows(sql"SELECT * FROM players"):
echo row
db.close()
- Output:
@["Smith, Steve", "42", "true", "99"]
Objeck
use IO;
use ODBC;
bundle Default {
class Sql {
function : Main(args : String[]) ~ Nil {
conn := Connection->New("ds", "user", "password");
if(conn <> Nil) {
sql := "UPDATE players SET name = ?, score = ?, active = ? WHERE jerseyNum = ?";
pstmt := conn->CreateParameterStatement(sql);
pstmt->SetVarchar(1, "Smith, Steve");
pstmt->SetInt(2, 42);
pstmt->SetBit(3, true);
pstmt->SetInt(4, 99);
pstmt->Update()->PrintLine();
conn->Close();
};
}
}
Pascal
Tested with Free Pascal 2.6.4 (arm) and SQLite 3.8.7.1
program Parametrized_SQL_Statement;
uses
sqlite3, sysutils;
const
DB_FILE : PChar = ':memory:'; // Create an in-memory database.
var
DB :Psqlite3;
ResultCode :Integer;
SQL :PChar;
InsertStatements :array [1..4] of PChar;
CompiledStatement :Psqlite3_stmt;
i :integer;
{ CheckError
Checks the result code from an SQLite operation.
If it contains an error code then this procedure prints the error message,
closes the database and halts the program. }
procedure CheckError(ResultCode: integer; DB: Psqlite3);
begin
if ResultCode <> SQLITE_OK then
begin
writeln(format('Error #%d: %s', [ResultCode, sqlite3_errmsg(db)]));
sqlite3_close(DB);
halt(ResultCode);
end;
end;
{ SelectCallback
This callback function prints the results of the select statement.}
function SelectCallback(Data: pointer; ColumnCount: longint; Columns: PPChar; ColumnNames: PPChar):longint; cdecl;
var
i :longint;
col :PPChar;
begin
col := Columns;
for i:=0 to ColumnCount-1 do
begin
write(col^); // Print the current column value.
inc(col); // Advance the pointer.
if i<>ColumnCount-1 then write(' | ');
end;
writeln;
end;
begin
// Open the database.
ResultCode := sqlite3_open(DB_FILE, @DB);
CheckError(ResultCode, DB);
// Create the players table in the database.
SQL := 'create table players(' +
'id integer primary key asc, ' +
'name text, ' +
'score real, ' +
'active integer, ' + // Store the bool value as integer (see https://sqlite.org/datatype3.html chapter 2.1).
'jerseyNum integer);';
ResultCode := sqlite3_exec(DB, SQL, nil, nil, nil);
CheckError(ResultCode, DB);
// Insert some values into the players table.
InsertStatements[1] := 'insert into players (name, score, active, jerseyNum) ' +
'values (''Roethlisberger, Ben'', 94.1, 1, 7);';
InsertStatements[2] := 'insert into players (name, score, active, jerseyNum) ' +
'values (''Smith, Alex'', 85.3, 1, 11);';
InsertStatements[3] := 'insert into players (name, score, active, jerseyNum) ' +
'values (''Manning, Payton'', 96.5, 0, 18);';
InsertStatements[4] := 'insert into players (name, score, active, jerseyNum) ' +
'values (''Doe, John'', 15, 0, 99);';
for i:=1 to 4 do
begin
ResultCode := sqlite3_exec(DB, InsertStatements[i], nil, nil, nil);
CheckError(ResultCode, DB);
end;
// Display the contents of the players table.
writeln('Before update:');
SQL := 'select * from players;';
ResultCode := sqlite3_exec(DB, SQL, @SelectCallback, nil, nil);
CheckError(ResultCode, DB);
// Prepare the parametrized SQL statement to update player #99.
SQL := 'update players set name=?, score=?, active=? where jerseyNum=?;';
ResultCode := sqlite3_prepare_v2(DB, SQL, -1, @CompiledStatement, nil);
CheckError(ResultCode, DB);
// Bind the values to the parameters (see https://sqlite.org/c3ref/bind_blob.html).
ResultCode := sqlite3_bind_text(CompiledStatement, 1, PChar('Smith, Steve'), -1, nil);
CheckError(ResultCode, DB);
ResultCode := sqlite3_bind_double(CompiledStatement, 2, 42);
CheckError(ResultCode, DB);
ResultCode := sqlite3_bind_int(CompiledStatement, 3, 1);
CheckError(ResultCode, DB);
ResultCode := sqlite3_bind_int(CompiledStatement, 4, 99);
CheckError(ResultCode, DB);
// Evaluate the prepared SQL statement.
ResultCode := sqlite3_step(CompiledStatement);
if ResultCode <> SQLITE_DONE then
begin
writeln(format('Error #%d: %s', [ResultCode, sqlite3_errmsg(db)]));
sqlite3_close(DB);
halt(ResultCode);
end;
// Destroy the prepared statement object.
ResultCode := sqlite3_finalize(CompiledStatement);
CheckError(ResultCode, DB);
// Display the contents of the players table.
writeln('After update:');
SQL := 'select * from players;';
ResultCode := sqlite3_exec(DB, SQL, @SelectCallback, nil, nil);
CheckError(ResultCode, DB);
// Close the database connection.
sqlite3_close(db);
end.
- Output:
Before update: 1 | Roethlisberger, Ben | 94.1 | 1 | 7 2 | Smith, Alex | 85.3 | 1 | 11 3 | Manning, Payton | 96.5 | 0 | 18 4 | Doe, John | 15.0 | 0 | 99 After update: 1 | Roethlisberger, Ben | 94.1 | 1 | 7 2 | Smith, Alex | 85.3 | 1 | 11 3 | Manning, Payton | 96.5 | 0 | 18 4 | Smith, Steve | 42.0 | 1 | 99
Perl
use DBI;
my $db = DBI->connect('DBI:mysql:mydatabase:host','login','password');
$statment = $db->prepare("UPDATE players SET name = ?, score = ?, active = ? WHERE jerseyNum = ?");
$rows_affected = $statment->execute("Smith, Steve",42,'true',99);
Phix
-- -- demo\rosetta\Parameterized_SQL_statement.exw -- ============================================ -- without js -- (pSQLite) include pSQLite.e --<some pretty printing, not really part of the demo> constant {coltypes,colfmts,colrids} = columnize({ {SQLITE_INTEGER,"%4d",sqlite3_column_int}, {SQLITE_FLOAT,"%4g",sqlite3_column_double}, {SQLITE_TEXT,"%-20s",sqlite3_column_text}}) procedure show(string what, sqlite3 db) printf(1,"%s:\n",{what}) sqlite3_stmt pStmt = sqlite3_prepare(db,"SELECT * FROM players;") while 1 do integer res = sqlite3_step(pStmt) if res=SQLITE_DONE then exit end if assert(res=SQLITE_ROW) string text = "" for c=1 to sqlite3_column_count(pStmt) do integer ctype = sqlite3_column_type(pStmt,c), cdx = find(ctype,coltypes), rid = colrids[cdx] string name = sqlite3_column_name(pStmt,c), data = sprintf(colfmts[cdx],rid(pStmt,c)) text &= sprintf(" %s:%s",{name,data}) end for printf(1,"%s\n",{text}) end while assert(sqlite3_finalize(pStmt)=SQLITE_OK) end procedure --</pretty printing> sqlite3 db = sqlite3_open(":memory:") assert(sqlite3_exec(db,`create table players (name, score, active, jerseyNum)`)=SQLITE_OK) assert(sqlite3_exec(db,`insert into players values ('Roethlisberger, Ben', 94.1, 1, 7 )`)=SQLITE_OK) assert(sqlite3_exec(db,`insert into players values ('Smith, Alex', 85.3, 1, 11)`)=SQLITE_OK) assert(sqlite3_exec(db,`insert into players values ('Doe, John', 15, 0, 99)`)=SQLITE_OK) assert(sqlite3_exec(db,`insert into players values ('Manning, Payton', 96.5, 0, 123)`)=SQLITE_OK) show("Before",db) --pp({"Before",sqlite3_get_table(db, "select * from players")},{pp_Nest,2}) -- For comparison against some other entries, this is how you would do numbered parameters: --/* sqlite3_stmt pStmt = sqlite3_prepare(db, `update players set name=?, score=?, active=? where jerseyNum=?`) sqlite3_bind_text(pStmt,1,"Smith, Steve") sqlite3_bind_double(pStmt,2,42) sqlite3_bind_int(pStmt,3,true) sqlite3_bind_int(pStmt,4,99) --*/ -- However, ordinarily I would prefer named parameters and sqlbind_parameter_index() calls: sqlite3_stmt pStmt = sqlite3_prepare(db, `update players set name=:name, score=:score, active=:active where jerseyNum=:jerseyn`) constant k_name = sqlite3_bind_parameter_index(pStmt, ":name"), k_score = sqlite3_bind_parameter_index(pStmt, ":score"), k_active = sqlite3_bind_parameter_index(pStmt, ":active"), k_jerseyn = sqlite3_bind_parameter_index(pStmt, ":jerseyn") sqlite3_bind_text(pStmt,k_name,"Smith, Steve") sqlite3_bind_double(pStmt,k_score,42) sqlite3_bind_int(pStmt,k_active,true) sqlite3_bind_int(pStmt,k_jerseyn,99) assert(sqlite3_step(pStmt)=SQLITE_DONE) assert(sqlite3_finalize(pStmt)=SQLITE_OK) show("After",db) --pp({"After",sqlite3_get_table(db, "select * from players")},{pp_Nest,2}) sqlite3_close(db)
- Output:
Before: name:Roethlisberger, Ben score:94.1 active: 1 jerseyNum: 7 name:Smith, Alex score:85.3 active: 1 jerseyNum: 11 name:Doe, John score: 15 active: 0 jerseyNum: 99 name:Manning, Payton score:96.5 active: 0 jerseyNum: 123 After: name:Roethlisberger, Ben score:94.1 active: 1 jerseyNum: 7 name:Smith, Alex score:85.3 active: 1 jerseyNum: 11 name:Smith, Steve score: 42 active: 1 jerseyNum: 99 name:Manning, Payton score:96.5 active: 0 jerseyNum: 123
PHP
$updatePlayers = "UPDATE `players` SET `name` = ?, `score` = ?, `active` = ?\n".
"WHERE `jerseyNum` = ?";
$dbh = new PDO( "mysql:dbname=db;host=localhost", "username", "password" );
$updateStatement = $dbh->prepare( $updatePlayers );
$updateStatement->bindValue( 1, "Smith, Steve", PDO::PARAM_STR );
$updateStatement->bindValue( 2, 42, PDO::PARAM_INT );
$updateStatement->bindValue( 3, 1, PDO::PARAM_INT );
$updateStatement->bindValue( 4, 99, PDO::PARAM_INT );
$updateStatement->execute();
// alternatively pass parameters as an array to the execute method
$updateStatement = $dbh->prepare( $updatePlayers );
$updateStatement->execute( array( "Smith, Steve", 42, 1, 99 ) );
PicoLisp
As PicoLisp uses normal function calls for DB manipulations, parameters are always treated as plain data and are not executed.
(for P (collect 'jerseyNum '+Players 99)
(put!> P 'name "Smith, Steve")
(put!> P 'score 42)
(put!> P 'active T) )
Python
import sqlite3
db = sqlite3.connect(':memory:')
# setup
db.execute('create temp table players (name, score, active, jerseyNum)')
db.execute('insert into players values ("name",0,"false",99)')
db.execute('insert into players values ("name",0,"false",100)')
# demonstrate parameterized SQL
# example 1 -- simple placeholders
db.execute('update players set name=?, score=?, active=? where jerseyNum=?', ('Smith, Steve', 42, True, 99))
# example 2 -- named placeholders
db.execute('update players set name=:name, score=:score, active=:active where jerseyNum=:num',
{'num': 100,
'name': 'John Doe',
'active': False,
'score': -1}
)
# and show the results
for row in db.execute('select * from players'):
print(row)
outputs
(u'Smith, Steve', 42, 1, 99) (u'John Doe', -1, 0, 100)
Racket
#lang racket/base
(require sql db)
(define pgc
; Don't actually inline sensitive data ;)
(postgresql-connect #:user "resu"
#:database "esabatad"
#:server "example.com"
#:port 5432
#:password "s3>r37P455"))
(define update-player
(parameterize ((current-sql-dialect 'postgresql))
(update players
#:set [name ?] [score ?] [active ?]
#:where [jerseyNum ?])))
(apply query
pgc
update-player
'("Smith, Steve" 42 #t 99))
Raku
(formerly Perl 6)
use DBIish;
my $db = DBIish.connect('DBI:mysql:mydatabase:host','login','password');
my $update = $db.prepare("UPDATE players SET name = ?, score = ?, active = ? WHERE jerseyNum = ?");
my $rows-affected = $update.execute("Smith, Steve",42,'true',99);
Ruby
Using the
gem
require 'sqlite3'
db = SQLite3::Database.new(":memory:")
# setup
db.execute('create temp table players (name, score, active, jerseyNum)')
db.execute('insert into players values ("name",0,"false",99)')
db.execute('insert into players values ("name",0,"false",100)')
db.execute('insert into players values ("name",0,"false",101)')
# demonstrate parameterized SQL
# example 1 -- simple placeholders
db.execute('update players set name=?, score=?, active=? where jerseyNum=?', 'Smith, Steve', 42, true, 99)
# example 2 -- named placeholders
db.execute('update players set name=:name, score=:score, active=:active where jerseyNum=:num',
:num => 100,
:name => 'John Doe',
:active => false,
:score => -1
)
# example 3 -- numbered placeholders
stmt = db.prepare('update players set name=?4, score=?3, active=?2 where jerseyNum=?1')
stmt.bind_param(1, 101)
stmt.bind_param(2, true)
stmt.bind_param(3, 3)
stmt.bind_param(4, "Robert'; DROP TABLE players--")
stmt.execute
# and show the results
db.execute2('select * from players') {|row| p row}
outputs
["name", "score", "active", "jerseyNum"] ["Smith, Steve", "42", "true", "99"] ["John Doe", "-1", "false", "100"] ["Robert'; DROP TABLE players--", "3", "true", "101"]
Scala
Using Slick FRM
- Output:
Best seen running in your browser Scastie (remote JVM).
import slick.jdbc.H2Profile.api._
import slick.sql.SqlProfile.ColumnOption.SqlType
import scala.concurrent.Await
import scala.concurrent.ExecutionContext.Implicits.global
import scala.concurrent.duration.Duration
object PlayersApp extends App {
lazy val playerRecords = TableQuery[PlayerRecords]
val db = Database.forURL("jdbc:h2:mem:test1;DB_CLOSE_DELAY=-1", driver = "org.h2.Driver")
// Pre-compiled parameterized statement
val compiledUpdate = Compiled { jerseyN: Rep[Int] =>
for {c <- playerRecords if c.jerseyNum === jerseyN} yield (c.name, c.score, c.active)
}
def setup = DBIO.seq(
playerRecords.schema.create,
playerRecords ++= Seq( // JDBC batch update
(7, "Roethlisberger, Ben", 94.1f, true),
(11, "Smith, Alex", 85.3f, true),
(18, "Manning, Payton", 96.5f, false),
(99, "Doe, John", 15f, false))
)
def queryPlayers(prelude: String) = {
println("\n " +prelude)
println(
"│ Name │Scor│ Active │Jerseynum│\n" +
"├───────────────────────────────┼────┼────────┼─────────┤"
)
DBIO.seq(playerRecords.result.map(_.map {
case (jerseyN, name, score, active) =>
f"$name%32s $score ${(if (active) "" else "in") + "active"}%8s $jerseyN%8d"
}.foreach(println)))
}
// Definition of the PLAYERS table
class PlayerRecords(tag: Tag) extends Table[(Int, String, Float, Boolean)](tag, "PLAYER_RECORDS") {
def active = column[Boolean]("ACTIVE")
def jerseyNum = column[Int]("JERSEY_NUM", O.PrimaryKey)
def name = column[String]("NAME", SqlType("VARCHAR2(32)"))
def score = column[Float]("SCORE")
def * = (jerseyNum, name, score, active)
}
println(s"The pre-compiled parameterized update DML:\n${compiledUpdate(0).updateStatement}")
Await.result(db.run(
for { // Using the for comprehension
_ <- setup
_ <- queryPlayers("Before update:")
n <- compiledUpdate(99).update("Smith, Steve", 42f, true)
_ <- queryPlayers("After update:")
} yield n), Duration.Inf)
}
Seed7
The library sql_base.s7i provides access to databases. The type database describes a database connection and the type sqlStatement can store a prepared statement. In the example below the table players is created and filled with hard coded SQL statements, that are executed without parametrization. The SQL statement to update the table uses parametrization. The SQL statement is prepared, parameters are bound and the statement is executed. Finally a SQL select statement is prepared, executed and the result rows are fetched. A column from a result row is retrieved with the function column.
$ include "seed7_05.s7i";
include "sql_base.s7i";
const proc: main is func
local
var database: testDb is database.value;
var sqlStatement: statement is sqlStatement.value;
var string: name is "Smith, Steve";
begin
testDb := openDatabase(DB_SQLITE, "test", "test", "test");
execute(testDb, "create table players (name CHAR(32), score INTEGER, active CHAR, jerseyNum INTEGER)");
execute(testDb, "insert into players values ('Jones, Bob',0,0,99)");
execute(testDb, "insert into players values ('Jesten, Jim',0,0,100)");
execute(testDb, "insert into players values ('Jello, Frank',0,0,101)");
statement := prepare(testDb, "update players set name = ?, score = ?, active = ? \
\where jerseyNum = ?");
bind(statement, 1, name);
bind(statement, 2, 42);
bind(statement, 3, TRUE);
bind(statement, 4, 99);
execute(statement);
statement := prepare(testDb, "select * from players");
execute(statement);
while fetch(statement) do
writeln(column(statement, 1, string) <& " " <&
column(statement, 2, integer) <& " " <&
column(statement, 3, boolean) <& " " <&
column(statement, 4, integer));
end while;
execute(testDb, "drop table players");
close(testDb);
end func;
- Output:
Smith, Steve 42 TRUE 99 Jesten, Jim 0 FALSE 100 Jello, Frank 0 FALSE 101
SQL
-- This works in Oracle's SQL*Plus command line utility
VARIABLE P_NAME VARCHAR2(20);
VARIABLE P_SCORE NUMBER;
VARIABLE P_ACTIVE VARCHAR2(5);
VARIABLE P_JERSEYNUM NUMBER;
begin
:P_NAME := 'Smith, Steve';
:P_SCORE := 42;
:P_ACTIVE := 'TRUE';
:P_JERSEYNUM := 99;
end;
/
drop table players;
create table players
(
NAME VARCHAR2(20),
SCORE NUMBER,
ACTIVE VARCHAR2(5),
JERSEYNUM NUMBER
);
insert into players values ('No name',0,'FALSE',99);
commit;
select * from players;
UPDATE players
SET name = :P_NAME, score = :P_SCORE, active = :P_ACTIVE
WHERE jerseyNum = :P_JERSEYNUM;
commit;
select * from players;
- Output:
SQL> SQL> NAME SCORE ACTIV JERSEYNUM -------------------- ---------- ----- ---------- No name 0 FALSE 99 SQL> SQL> 2 3 1 row updated. SQL> SQL> Commit complete. SQL> SQL> NAME SCORE ACTIV JERSEYNUM -------------------- ---------- ----- ---------- Smith, Steve 42 TRUE 99
SQL PL
The following example is indeed parameterized SQL with named placeholders and it prevents SQL injections, and the SQL performs very well, because the execution plan is also precompiled.
--#SET TERMINATOR @
CREATE TABLE PLAYERS (
NAME VARCHAR(32),
SCORE INT,
ACTIVE SMALLINT,
JERSEYNUM INT
) @
CREATE PROCEDURE UPDATE_PLAYER (
IN PLAYER_NAME VARCHAR(32),
IN PLAYER_SCORE INT,
IN PLAYER_ACTIVE SMALLINT,
IN JERSEY_NUMBER INT
)
BEGIN
UPDATE PLAYERS
SET NAME = PLAYER_NAME, SCORE = PLAYER_SCORE, ACTIVE = PLAYER_ACTIVE
WHERE JERSEYNUM = JERSEY_NUMBER;
END @
INSERT INTO PLAYERS VALUES ('Pele', '1280', 0, 10) @
CALL UPDATE_PLAYER ('Maradona', '600', 1, 10) @
SELECT * FROM PLAYERS @
Output:
db2 -td@ db2 => CREATE TABLE PLAYERS ( NAME VARCHAR(32), SCORE INT, ACTIVE SMALLINT, JERSEYNUM INT ) @ DB20000I The SQL command completed successfully. db2 => CREATE PROCEDURE UPDATE_PLAYER ( IN PLAYER_NAME VARCHAR(32), IN PLAYER_SCORE INT, IN PLAYER_ACTIVE SMALLINT, IN JERSEY_NUMBER INT ) BEGIN UPDATE PLAYERS SET NAME = PLAYER_NAME, SCORE = PLAYER_SCORE, ACTIVE = PLAYER_ACTIVE WHERE JERSEYNUM = JERSEY_NUMBER; END @ DB20000I The SQL command completed successfully. db2 => INSERT INTO PLAYERS VALUES ('Pele', '1280', 0, 10) @ DB20000I The SQL command completed successfully. db2 => CALL UPDATE_PLAYER ('Maradona', '600', 1, 10) @ Return Status = 0 db2 => SELECT * FROM PLAYERS @ NAME SCORE ACTIVE JERSEYNUM -------------------------------- ----------- ------ ----------- Maradona 600 1 10 1 record(s) selected.
Tcl
package require Tcl 8.6
# These next two lines are the only ones specific to SQLite
package require tdbc::sqlite3
set db [tdbc::sqlite3::connection new /path/to/database.sql]
# Use a helper procedure to make a scope
proc setPlayer {db jersey -> playerName playerScore playerActive} {
# Note that the '->' above is just syntactic noise for readability
$db allrows {
UPDATE players
SET name = :playerName, score = :playerScore, active = :playerActive
WHERE jerseyNum = :jersey
}
# The named parameters are bound to local variables by default
}
# How to use...
setPlayer $db 99 -> "Smith, Steve" 42 true
# With apologies to http://xkcd.com/327/
setPlayer $db 76 -> "Robert'; DROP TABLE players--" 0 false
$db close
Wren
An embedded program using our SQLite wrapper.
import "./sql" for Connection
var db = Connection.open("rc.db")
var createSql = [
"DROP TABLE IF EXISTS players",
"CREATE table players (name, score, active, jerseyNum)",
"INSERT INTO players VALUES ('Roethlisberger, Ben', 94.1, TRUE, 7)",
"INSERT INTO players VALUES ('Smith, Alex', 85.3, TRUE, 11)",
"INSERT INTO players VALUES ('Doe, John', 15, FALSE, 99)",
"INSERT INTO players VALUES ('Manning, Payton', 96.5, FALSE, 123)"
]
for (sql in createSql) db.exec(sql)
var widths = [22, 7, 7, 9]
System.print("Before update:\n")
db.printTable("SELECT * FROM players", widths)
var updateSql = "UPDATE players SET name = ?, score = ?, active = ? WHERE jerseyNum = 99"
var ps = db.prepare(updateSql)
ps.bindText(1, "Smith, Steve")
ps.bindDouble(2, 42)
ps.bindBool(3, true)
ps.bindInt(4, 99)
ps.step()
System.print("\nAfter update:\n")
db.printTable("SELECT * FROM players", widths)
- Output:
Before update: name score active jerseyNum ------------------------------------------------ Roethlisberger, Ben 94.1 1 7 Smith, Alex 85.3 1 11 Doe, John 15 0 99 Manning, Payton 96.5 0 123 After update: name score active jerseyNum ------------------------------------------------ Roethlisberger, Ben 94.1 1 7 Smith, Alex 85.3 1 11 Smith, Steve 42.0 1 99 Manning, Payton 96.5 0 123
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- 8051 Assembly/Omit
- 8086 Assembly/Omit
- ARM Assembly/Omit
- Computer/zero Assembly/Omit
- DIV Games Studio/Omit
- Jacquard Loom/Omit
- LC3 Assembly/Omit
- Maxima/Omit
- Minimal BASIC/Omit
- MIPS Assembly/Omit
- OASYS Assembler/Omit
- Palo Alto Tiny BASIC/Omit
- PARI/GP/Omit
- PDP-11 Assembly/Omit
- Pentium Assembly/Omit
- PL/0/Omit
- TI-83 BASIC/Omit
- TI-89 BASIC/Omit
- Tiny BASIC/Omit
- Unlambda/Omit
- VAX Assembly/Omit
- X86 Assembly/Omit
- XSLT 1.0/Omit
- Z80 Assembly/Omit