Table creation: Difference between revisions
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m[1,] = ["Barack", "Obama", 20500];
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=={{header|Perl 6}}==
In Perl 6, there is no 'database' type built in, so it is somewhat ambiguous when specifying 'create a database table'. Perl 6 offers bindings to most common databases through its DBIish module but mostly abstracts away the differences between the underlying databases, which hides many of the finer distinctions of what may be stored where. The actual data types and options available are properties of the database used.
If on the other hand, we are meant to show built in collective types that may be used to hold tabular data, this may be of some use.
In general, a container type can hold objects of any data type, even instances of their own type; allowing 'multi-dimensional' (tabular) containers.
Perl 6 offers two broad categories of collective container types; those that do the Positional role and those that do Associative. Positional objects are collective objects that access the individual storage slots using an integer index. Associative objects use some sort of other pointer (typically string) to access their storage slots.
The various Associative types mostly differ in their value handling. Hash, Map and QuantHash may have any type of object as their value. All the others have some specific, usually numeric, type as their value.
<pre>
Positional - Object that supports looking up values by integer index
Array Sequence of itemized objects
List Immutable sequence of objects
Associative - Object that supports looking up values by key (typically string)
Bag Immutable collection of distinct objects with integer weights
BagHash Mutable collection of distinct objects with integer weights
Hash Mapping from strings to itemized values
Map Immutable mapping from strings to values
Mix Immutable collection of distinct objects with Real weights
MixHash Mutable collection of distinct objects with Real weights
QuantHash Collection of objects represented as hash keys
Set Immutable collection of distinct objects, no value except 'present'
SetHash Mutable collection of distinct objects, no value except 'present'
</pre>
If you want a persistent instance of any of these types, you need to declare the name with some scope constraint, but the are no prerequisites to creating instances. Simply assigning values to them will call them into existence.
=={{header|PL/I}}==
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