IF Statement

Takes one code path or the other based on an SQL expression. The condition expression must evaluate to the integer 0 or 1.

Syntax

Parameters

• condition: integer (0-1)
  If this expression evaluates to 1, then the statement-if-true statements are executed. Otherwise, the statement-if-false statements are executed.
• statement-if-true: statement
  The statements to execute if the condition is 1. If more than one statement-if-true statement is desired, the BEGIN and END keywords must be used.
• statement-if-false: statement
  The statements to execute if the condition is 0. If more than one statement-if-false statement is desired, the BEGIN and END keywords must be used.

Example

DECLARE PARAMETER @foo = 111;
DECLARE PARAMETER @bar = 222;

-- The simplest IF tests a condition and executes a single
-- statement if true.
IF 1  -- Always true.
    PRINT 'Hi';  -- Always prints.

IF @foo = 123
    PRINT 'Hi';  -- Prints or not depending on @foo.

-- An ELSE block will run if the IF condition is false.
IF @foo > @bar
    PRINT 'Foo';
ELSE
    PRINT 'Bar';

-- Check a series of conditions with ELSE IF.
IF @foo = 111
    PRINT 'First condition'
ELSE IF @bar = 111
    PRINT 'Second condition'
ELSE IF @foo = 222 AND @bar = 222
    PRINT 'Third condition'
ELSE
    PRINT 'None of the above'

-- Add BEGIN and END to any block to execute multiple statements.
IF @foo = 111 BEGIN
    PRINT 'Hello...'
    PRINT 'World!'
END