Re: [HACKERS] JOIN between three *simple* tables ... - Mailing list pgsql-sql

"Marc G. Fournier" <scrappy@hub.org> writes:
> iwantu=# \d poc_uid
>  Index "poc_uid"
>  Column |  Type
> --------+--------
>  uid    | bigint
> btree

> iwantu=# explain select count(1) from orientation_c poc where uid = 1;
> NOTICE:  QUERY PLAN:

> Aggregate  (cost=2264.97..2264.97 rows=1 width=0)
>   ->  Seq Scan on orientation_c poc  (cost=0.00..2264.96 rows=1 width=0)

> EXPLAIN

You're forgetting ye olde constant-casting problem.  You need something
like
select count(1) from orientation_c poc where uid = 1::bigint;

to use an index on a bigint column.

Not sure about the other thing; have you VACUUM ANALYZEd (or at least
ANALYZEd) since filling the tables?  It looks like the system thinks
the tables are much smaller than they really are.
        regards, tom lane