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.