[DERBY-1575] document full syntax of CASE expression

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 10.2.1.6, 10.3.1.4
• Component/s: Documentation
• Assignee: Camilla Haase
• Reporter: Christian d'Heureuse
• Created: 23/Jul/06 12:34
• Updated: 19/Sep/06 17:20
• Resolved: 29/Aug/06 23:29

Description

The documentation at http://db.apache.org/derby/docs/dev/ref/rrefcasenullif.html describes the CASE expression syntax as:

CASE WHEN BooleanExpression THEN thenExpression ELSE elseExpression END

But the CASE expression supports more than one WHEN/THEN clauses.
I suggest to change the syntax description to:

CASE
WHEN BooleanExpression THEN Expression
[ WHEN BooleanExpression THEN Expression ]
...
ELSE elseExpression
END

Example:

VALUES
CASE
WHEN 1 = 2 THEN 3
WHEN 4 = 5 THEN 6
ELSE 7
END