Archives of the TeradataForum
Message Posted: Fri, 09 Jul 1999 @ 18:55:44 GMT
| Subj: || || Re: Product and Merge Joins |
| From: || || John Hall |
I spend a lot of time trying to get people to have more trust in the optimizer and reduce the dependence on 'tricks'. In the last couple
of years, the optimizer has gotten much better and far more effective in creating good workplans. Although it's not perfect, if you have
worked with the Teradata product for more than a couple of years, you've probably seen really big improvements. Instead of depending on
tricks which might 'break' with a future release, it might be better to see what's preventing the optimizer from doing a better job. If
there's a problem with the optimizer, it should be pursued as a bug and fixed by NCR.
Could you send the SQL for table ACCT_RC_ASSIGNMENT_VW? Have you collected statistics on the table and are they current? If they
haven't been collected, you might try that before anything else (you might send the HELP STATISTICS). Do you know the table demographics
(row count, the distribution of the data, etc). You might also send the EXPLAIN for the first query. BTW: What version are you using (if
you don't know, do: SEL * FROM DBC.DBCINFOTBL;).