The case statement is a Flow / Control Structure
PL/SQL provides two forms of case statement.
Like any PL/SQL blocks, CASE statements can be labeled.
The CASE statement:
[<<label_name>>]
CASE selector expression
WHEN expression1 THEN sequence_of_statements1;
WHEN expression2 THEN sequence_of_statements2;
...
WHEN expressionN THEN sequence_of_statementsN;
[ELSE sequence_of_statementsN+1;]
END CASE [label_name];
PL/SQL also provides a searched CASE statement.
The CASE statement:
[<<label_name>>]
CASE
WHEN selector expression1 THEN sequence_of_statements1;
WHEN selector expression2 THEN sequence_of_statements2;
...
WHEN selector expressionN THEN sequence_of_statementsN;
[ELSE sequence_of_statementsN+1;]
END CASE [label_name];
The selector expression