Sybase Adaptive Server Anywhere - IF Statement [T-SQL]

Chapter 9 SQL Statements
547
IF statement [T-SQL]
Use this statement to control conditional execution of a SQL statement, as an
alternative to the Watcom-SQL IF statement.
IF expression
… statement
… [ ELSE
… [ IF
expression ]
…
statement ]
None.
None.
The Transact-SQL IF conditional and the ELSE conditional each control the
execution of only a single SQL statement or compound statement (between
the keywords BEGIN and END).
In comparison to the Watcom-SQL IF statement, there is no THEN in the
Transact-SQL IF statement. The Transact-SQL version also has no ELSEIF
or END IF keywords.
♦
SQL/92 Transact-SQL extension.
♦
Sybase Adaptive Server Enterprise supports the Transact-SQL IF
statement.
♦ The following example illustrates the use of the Transact-SQL IF
statement:
IF (SELECT max(id) FROM sysobjects) < 100
RETURN
ELSE
BEGIN
PRINT "These are the user-created objects"
SELECT name, type, id
FROM sysobjects
WHERE id < 100
END
♦ The following two statement blocks illustrate Transact-SQL and
Watcom-SQL compatibility:
/* Transact-SQL IF statement */
IF @v1 = 0
PRINT ’0’
ELSE IF @v1 = 1
PRINT ’1’
ELSE
PRINT ’other’
/* Watcom-SQL IF statement */
Function
Syntax
Authorization
Side effects
Description
Standards and
compatibility
Example