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Message Posted: Tue, 01 Jun 2004 @ 22:00:03 GMT
| Subj: || || Re: Exclusion Joins |
| From: || || Christie, Jon |
NOT EXISTS is much better than NOT IN when there are multiple terms. With NOT IN, multiple terms, and nullable columns, you get very strange
explains with verbage about skipping steps. Basically, the amps decide at execution time which of too similar plans to use. There's a reason for
this that actually does make sense, but it's a rather long story.
The equivalent NOT EXISTS, though less intuitive to read, suffers from none of these problems.