Re: count * performance issue

["sathiya psql" <sathiya.psql@xxxxxxxxx>]

                                                          QUERY PLAN
------------------------------------------------------------------------------------------------------------------------------
 Aggregate  (cost=205756.95..205756.95 rows=1 width=0) (actual time=114675.042..114675.042 rows=1 loops=1)
   ->  Seq Scan on call_log  (cost=0.00..193224.16 rows=5013112 width=0) (actual time=11.754..91429.594 rows=5061619 loops=1)
         Filter: (call_id > 0)
 Total runtime: 114699.797 ms
(4 rows)


it is now taking 114 seconds, i think because of load in my system.... any way will you explain., what is this COST, actual time and other stuffs....

On Thu, Mar 6, 2008 at 12:27 PM, A. Kretschmer <andreas.kretschmer@xxxxxxxxxxxxxx> wrote:

am  Thu, dem 06.03.2008, um 12:17:55 +0530 mailte sathiya psql folgendes:

> TRIGGER i can use if i want the count of the whole table, but i require for
> some of the rows with WHERE condition....
>
> so how to do that ???

Okay, in this case a TRIGGER are a bad idea. You can use an INDEX on
this row. Can you show us the output for a EXPLAIN ANALYSE SELECT
count(*) from <your_table> WHERE <your_row> = ... ?

Andreas
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