Scott Ribe <scott_ribe@killerbytes.com> writes:
>> The time the DB needs to find the record
>> should be the same since the record has to be found before the resultset is
>> assembled.
>
> What if the query can be satisfied from an index? I don't know if PostgreSQL
> has this kind of optimization or not.
Nope. Tuple visibility isn't stored in indexes, so it still has to
visit the heap to see if a row is visible to your transaction.
-Doug