[DERBY-2441] The documentation for NULLIF could be improved

• Type: Task
• Status: Closed
• Priority: Trivial
• Resolution: Invalid
• Affects Version/s: 10.3.1.4
• Component/s: Documentation
• Assignee: Unassigned
• Reporter: Katherine Marsden
• Created: 10/Mar/07 00:31
• Updated: 13/Mar/07 21:43
• Resolved: 13/Mar/07 21:43

Description

The documentation for NULLIF could be improved as it doesn't explain what NULLIF does at
http://db.apache.org/derby/manuals/reference/sqlj66.html#NULLIF+and+CASE+expressions
I believe the behaviour is that if both arguments are equal it returns NULL otherwise it returns the first value

e.g.
NULLIF(L, R)
is equivalent to:
CASE WHEN L=R THEN NULL ELSE L END