case Expression

case expression simplifies many conditional Transact-SQL constructs. Instead of using a series of if statements, case expression allows you to use a series of conditions that return the appropriate values when the conditions are met. case expression is ANSI-SQL-compliant.

With case expression, you can:

case expression includes the keywords case, when, then, coalesce, and nullif. coalesce and nullif are an abbreviated form of case expression. See the Reference Manual: Commands.