[DERBY-5557] NULLIF topic in reference manual should explain NULLIF

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 10.8.2.2
• Fix Version/s: 10.9.1.0
• Component/s: Documentation
• Assignee: Camilla Haase
• Reporter: Knut Anders Hatlen
• Created: 24/Dec/11 21:09
• Updated: 17/Apr/12 13:03
• Resolved: 12/Apr/12 17:38

Description

The section describing NULLIF in the reference manual is a bit cryptic. http://db.apache.org/derby/docs/10.8/ref/rrefcasenullif.html

It says that NULLIF is used for conditional expressions, and that it is similar to CASE, but it doesn't say in plain words how it works. It would be good if it could mention that NULLIF returns NULL if the two arguments are equal, and that it returns the first argument if they are not equal.