> Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> writes:
> > But what about '%A%' vs. '%AC%'. Seems the second is reasonably
> > different from the first the our optimizer may be fine with that. Is it
> > only when the strings get longer that we lose specificity?
> Yeah, I don't think that the estimates are bad for one or two
> characters. But the estimate gets real small real fast as you
> increase the number of match characters in the LIKE pattern.
> We need to slow that down some.
See my earlier email about the 50% idea for LIKE. Do ordinary string
comparisons also have this problem?
Bruce Momjian | http://candle.pha.pa.us
pgman(at)candle(dot)pha(dot)pa(dot)us | (610) 853-3000
+ If your life is a hard drive, | 830 Blythe Avenue
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