Re: [GENERAL] Problem (bug?) with like

> Bruce Momjian  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?

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