Re: Re: Query > 1000× slowdown after adding datetime comparison

林士博 wrote
> I think you should try putting the precomputed boolean temp_eval column
> to "EXTERNAL_TRANSLATION" r table.
>
> And if possible, try creating a conditional index on id where temp_eval is
> true,
> on "EXTERNAL_TRANSLATION" r table.
>
> So that, only check this index can get the top 1000 records.

I agree that might help. But I would still like to understand what's the
reason for difference between the second and the third query. Both contain a
simple <column> = <constant> expression, yet one finishes immediately and
one runs for 41 minutes.




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