IIF(...) not a recognized built-in function

Question

I'm trying to use this in Microsoft SQL Server 2008 R2:

SET @SomeVar = @SomeOtherVar +   IIF(@SomeBool, 'value when true', 'value when false') 

But I get an error:

IIF(...) is not a recognized built-in function name

Is IIF() only compatible with a later version?

Is there an alternate function I can use?

Answer 1

IIF comes from SQL 2012. Before then, you can use CASE:

SET @SomeVar = @SomeOtherVar + CASE  WHEN @SomeBool  THEN 'value when true'  ELSE 'value when false' END 

Answer 2

What's New in SQL Server 2012, Programmability Enhancements:

SQL Server 2012 introduces 14 new built-in functions. These functions ease the path of migration for information workers by emulating functionality that is found in the expression languages of many desktop applications. However these functions will also be useful to experienced users of SQL Server.

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• IIF (Transact SQL)