"Junaili Lie" <junaili@gmail.com> writes:
> we encounter issues when deleting from a table based on id (primary key). O=
> n
> certain 'id', it took forever to delete and the i/o is 100% busy.
Almost always, if delete is slow when selecting the same rows is fast,
it's because you've got a trigger performance problem --- most commonly,
there are foreign keys referencing this table from other tables and you
don't have the referencing columns indexed.
regards, tom lane