Re: "not in" clause too slow?

Ottavio Campana  írta:

> mytable.id is primary key.
> 
> I create copy_mytable with
> create table copy_mytable as (select * from mytable);
> 
> the planer behavior does not change no matter if I create and index
> on copy_mytable.id or not.


Try this, with an index on copy_mytable.id:

SELECT orig.* FROM mytable AS orig WHERE NOT EXISTS (
  SELECT 1 FROM copy_mytable AS copy WHERE copy.id = orig.id
);


Regards,
Denes Daniel

Olvasd az [origo]-t a mobilodon: mini magazinok a Mobizin-en
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