SQL Server/T-SQL Tutorial/Data Convert Functions/NULLIF

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Returning a NULL Value When Two Expressions Are Equal: Otherwise Return the First Expression

   <source lang="sql">

5> DECLARE @Value1 int 6> DECLARE @Value2 int 7> SET @Value1 = 55 8> SET @Value2 = 955 9> SELECT NULLIF(@Value1, @Value2) 10> GO


        55

(1 rows affected) 1> 2> 3> DECLARE @Value1 int 4> DECLARE @Value2 int 5> SET @Value1 = 55 6> SET @Value2 = 55 7> SELECT NULLIF(@Value1, @Value2) 8> GO


      NULL

(1 rows affected) 1></source>