The CASE statement goes through conditions and returns a value when the first condition is TRUE (similar to IF-THEN-ELSE statement).

Case statement can be used in select queries along with Where, Order By and Group By clause. It can also be used in the Insert statement.

SQL CASE Syntax:

CASE

    WHEN condition1 THEN result1

    WHEN condition2 THEN result2

    WHEN conditionN THEN resultN

    ELSE result

END

Example:

Lets use the “Products” table to shorten the name of the “SupplierName” for suppliers named “TechOne” and “TechThree”.

Results:

TechOne and TechThree are changed to a shorter name and TechTwo retains its original format.

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