Case is a conditional SQL expression: It searches for the first when clause that has the same value as the case clause and returns the value of the corresponding then clause—or that of else if nothing matches.
SELECT CASE column_name WHEN 0 THEN 'zero'
WHEN 1 THEN 'one'
ELSE 'not zero or one'
END
FROM …Related
Tutorial:
Case— Conditional ExpressionsA more generic
casesyntax:case when <condition>(searched case)Product specific features:
if,decode.
Normative References
The simple case expression is defined in ISO/IEC 9075:2016-2 as mandatory feature F261-01.
