Re: AW: AW: Is stats update during COPY IN really a good id ea?

> I actually do get perfect query plans without any stats, because
> our indexes are perfectly matched to our statements, and in two
> cases we tuned the sql appropriately (2 of >200 statements with
> Informix optimizer hints). For such a condition you actually
> want a rule based optimizer. The current default values during
> create table are more or less chosen to give exactly this "rule
> based" behavior. The trouble is, that after the first implicitly
> created stats, the optimizer goes completely bananas, because
> now he thinks that one table has 1000 (the default) rows (it
> actually has 10000000), but the other has 100000 and the optimizer
> now knows that and chooses a different plan. And just because
> you copy a few rows ?

Oh, that is interesting. You didn't explicitly ask for stats, but got
them anyway and that caused a problem.

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