Dirk Lutzebaeck writes:
>
> Hi,
>
> say I have three tables a,b,c with lots of columns (say 10 for each
> table). Using psql command line, why does
>
> SELECT a.*,b.*,c.* FROM a,b,c
>
> takes much more longer (in my specifc case 3 times) than only
> selecting one column like
>
> SELECT a.oid, b.oid, c.oid FROM a,b,c.
>
> This is on 7.0. Can I play with buffer sizes? Indexes exist on most
> of the columns. Columns in the second line can be arbitrary.
Two things two add:
- EXPLAIN shosw the same results in both cases
- currently I was working with ~ 500 rows
Dirk