Running a trivial query in v7.4.2 (installed with fedora core2) using
EXPLAIN ANALYZE is taking considerably longer than just running the query
(2mins vs 6 secs). I was using this query to quickly compare a couple of
systems after installing a faster disk.
Is this sort of slowdown to be expected?
Here's the query:
----------------------------------------
[chris@fedora tmp]$ time psql dbt << ENDSQL
> select count(*) from etab;
> ENDSQL
count
---------
9646782
(1 row)
real 0m6.532s
user 0m0.005s
sys 0m0.002s
[chris@fedora tmp]$ time psql dbt << ENDSQL
> explain analyze select count(*) from etab;
> ENDSQL
QUERY PLAN
----------------------------------------------------------------------------
---------------
-----------------------------
Aggregate (cost=182029.78..182029.78 rows=1 width=0) (actual
time=112701.488..112701.493
rows=1 loops=1)
-> Seq Scan on etab (cost=0.00..157912.82 rows=9646782 width=0) (actual
time=0.053..578
59.120 rows=9646782 loops=1)
Total runtime: 112701.862 ms
(3 rows)
real 1m52.716s
user 0m0.003s
sys 0m0.005s
---------------------------------------
Thanks in advance for any clues.
Chris Hutchinson