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Subject: =?UTF-8?Q?Re:__Re:_Query_>_1000=C3=97_slow?=
 =?UTF-8?Q?down_after_adding_datetime_comparison?=
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=E6=9E=97=E5=A3=AB=E5=8D=9A wrote
> I think you should try putting the precomputed boolean temp_eval column
> to "EXTERNAL_TRANSLATION" r table.
>=20
> And if possible, try creating a conditional index on id where temp_eval is
> true,
> on "EXTERNAL_TRANSLATION" r table.
>=20
> 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> =3D <constant> expression, yet one finishes immediately and
one runs for 41 minutes.




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