Re: [SQLObject] PostgreSQL: costly count

[Sidnei da S. <si...@aw...>]

| >>>
| example:
| On our message boards each post is a row.  The powers that be like to 
| know
| how many posts there are total (In addition to 'today')-
| select count(*) from posts is how it has been
| done on our informix db.  With our port to PG I instead select reltuples
| pg_class.
| <<<
| 
| pg_class is a mysterious table indeed, but it's got lots of good magic 
| in it.  (I'm not even sure if this is the right magic, but worth a try)

Humm... It seems to be the right one, but how can I measure which one
is faster? In my 11k table, both are blazingly fast :)

zope3=# select reltuples from pg_class where relname = 'aliquot';
 reltuples 
-----------
     11801
(1 row)

zope3=# select count(*) from aliquot;
 count 
-------
 11801
(1 row)


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