Use if statement to check a variable : Variable « Transact SQL « SQL Server / T-SQL Tutorial

4>    CREATE TABLE #VersionTable(
5>       [Index] int PRIMARY KEY,
6>       Name varchar(30),
7>       Internal_Value int,
8>       Character_Value varchar(250)
9>    )
10>    GO
1>
2>    INSERT INTO #VersionTable
3>    EXEC master..xp_msver
4>
5>    DECLARE @Version int
6>
7>    SELECT @Version = (SELECT Internal_Value
8>                                 FROM #VersionTable
9>                                 WHERE Name = 'ProductVersion')
10>    IF (@Version) >= 524288
11>       PRINT 'Running SS2K Beta 2 or Later'
12>    ELSE
13>       IF @Version >= 458752
14>          PRINT 'Running 7.0 RTM or Later'
15>       ELSE
16>          PRINT 'Running Pre 7.0 RTM Version'
17> GO

(20 rows affected)

(20 rows affected)
Running SS2K Beta 2 or Later
1>    DROP TABLE #VersionTable
2> GO

20.2.Variable
	20.2.1.	Working with Variables
	20.2.2.	Use right function with a variable
	20.2.3.	Testing the ISNULL function
	20.2.4.	SELECT LEFT(@FullName, 5)
	20.2.5.	Global variable names begin with an @@ prefix.
	20.2.6.	XML type variable
	20.2.7.	Varchar type variable
	20.2.8.	Use if statement to check a variable
	20.2.9.	A variable can be assigned a value from a subquery
	20.2.10.	Use aggregate function with variables
	20.2.11.	Use Local Variables in where clause
	20.2.12.	A SQL script that uses variables
	20.2.13.	Local variables used for searches
	20.2.14.	Pass variable to a user-defined function
	20.2.15.	Use one variables in like function