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> > This is caused by a semi-well known weakness in the optimizer.
> > The optimizer
> > rewrites the WHERE clause in conjunctive normal form (CNF):
> > (A and B) or (C and D) ==> (A or C) and (A or D) and (B or C)
> > and (B or D)
> Wouldn't disjunctive normal form be better, since it can be implemented as
> the simple union of a set of small queries?
Please tell us more.
Bruce Momjian | http://www.op.net/~candle
maillist(at)candle(dot)pha(dot)pa(dot)us | (610) 853-3000
+ If your life is a hard drive, | 830 Blythe Avenue
+ Christ can be your backup. | Drexel Hill, Pennsylvania 19026
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