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Hi Ed,
NULL Values are not stored in a btree index. Therefor, if you ask '... where
colum is null', the index is unusable.
A usual workaround is to use a dummy value, which semantically represents
NULL, e.g. Jan. 1st 1900 for a
unknown time value.
Regards
Stephan
Received on Tue Apr 23 2002 - 03:55:50 CDT