Archives of the TeradataForum
Message Posted: Wed, 08 Jan 2004 @ 00:41:19 GMT
| Subj: || || Re: View Performance |
| From: || || Victor Sokovin |
| ||There is a transitive term to be derived here:|| |
| ||RECJOB.JOB_ID = RECMTD.JOB_ID|| |
| ||This term would allow the optimizer to consider joining RECJOB to RECMTD. That may or may not be a wonderful thing, but as the request was
originally coded, that join would not even be considered. When the request is re-coded as above, the join would be considered.|| |
Could you clarify this part for me? Are the following points correct:
1. It was the intention for the optimizer to always consider the transitive closure for inner join predicates. Because of the bug
you mentioned only the 'old fashioned' syntax will be parsed as desired. ANSI 'JOIN' syntax implies no transitive closure.
2. Transitive closure will not be used for outer joins, and the bug does not affect that.