Merge 'trunk' into 'sybase'

Merge 'trunk' into 'sybase'

r20647@hlagh (orig r7659):  ribasushi | 2009-09-14 12:24:44 -0400
Someone claimed this is a problem...
r20650@hlagh (orig r7662):  ribasushi | 2009-09-15 03:43:46 -0400
Warn when distinct is used with group_by
r20651@hlagh (orig r7663):  rbuels | 2009-09-15 16:45:32 -0400
doc patch, clarified warning about using find_or_create() and friends on tables with auto-increment or similar columns
r20652@hlagh (orig r7664):  rbuels | 2009-09-15 16:55:15 -0400
another doc clarification regarding auto-inc columns with find_or_create() and such functions