NULLIF - Amazon Kinesis Data Analytics
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NULLIF

NULLIF ( <value-expression>, <value-expression> )

Returns null if the two input arguments are equal, otherwise returns the first value. Both arguments must be of comparable type, or an exception is raised.

Examples

Function Result

NULLIF(4,2)

4

NULLIF(4,4)

<null>

NULLIF('amy','fred')

amy

NULLIF('amy', cast(null as varchar(3)))

amy

NULLIF(cast(null as varchar(3)),'fred')

<null>