Data Types and Variables in AL

Master primitive and complex AL data types, variable declaration, and initialization patterns.

25 minBeginner

Learning Objectives

Use primitive types — Integer, Decimal, Boolean, Text, DateTime
Work with complex types — Record, Array, Option/Enum
Declare and initialize variables correctly in AL

Primitive Data Types

AL supports these fundamental data types:

Type	Purpose	Example
`Integer`	Whole numbers	`Count: Integer`
`Decimal`	Numbers with fractions	`Amount: Decimal`
`Boolean`	True/False	`IsActive: Boolean`
`Text`	Strings (fixed length)	`Name: Text[100]`
`Code`	Alphanumeric codes	`CustomerNo: Code[20]`
`Date`	Calendar dates	`PostingDate: Date`
`DateTime`	Date and time	`CreatedAt: DateTime`
`GUID`	Globally unique identifier	`RecordId: Guid`

Complex Data Types

Type	Purpose
`Record`	Represents a row in a table
`Array`	Collection of elements of the same type
`Option` / `Enum`	Predefined set of values (Enum preferred in modern AL)

Variable Declaration

Variables are declared with the var keyword:

VariableExamples.Codeunit.al

procedure ProcessCustomer()
var
    CustomerName: Text[100];
    TotalAmount: Decimal;
    IsProcessed: Boolean;
    CustomerRec: Record Customer;
begin
    CustomerName := 'Contoso Ltd.';
    TotalAmount := 1000.50;
    IsProcessed := false;
end;

Text Length

Always specify Text length: Text[100] not Text. Unbounded Text is only used in specific scenarios.

Record Variables

Record variables are the most common complex type — they represent table rows:

var
    SalesHeader: Record "Sales Header";
    SalesLine: Record "Sales Line";
begin
    if SalesHeader.Get(SalesHeader."Document Type"::Order, 'SO-001') then
        Message('Found order for %1', SalesHeader."Sell-to Customer Name");
end;

Enum vs Option

Modern AL uses Enum instead of legacy Option:

enum 50100 "Approval Status"
{
    value(0; Open) { }
    value(1; Approved) { }
    value(2; Rejected) { }
}

Option is Legacy

Option fields still exist in the base application but new development should use Enum objects.

Key Revision Points (MB-820)

Know primitive vs complex data types
Record variables are used for all table operations
Enum replaces Option in modern AL development