> Bruce Momjian <pgman@candle.pha.pa.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.
Yea, maybe a log base 2 decrease:
1 char 1x
2 char 2x
4 char 3x
8 char 4x
16 char 5x
--
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