From: Nathan Suderman <Nathan@pollstar.com>
To: pgsql-sql@postgresql.org
Subject: queries got slower using 7.1.3
Date: Thu, 25 Jul 2002 09:55:25 -0700
Message-ID: <sd3fcb17.081@groupwise6.pollstar.com> (raw)
I have a weird problem and don't even know where to begin. First let me
explain what is going on.
I am developing on a Postgres 7.1.3 box and found this unexplainable
delay on this query
select * from webfinal where w_artistkey = 'MICBUR' order by w_date
offset 2 limit 4;
I get at least a 8-9 second delay. If I take either the 'order by' or
the 'limit' off the results are immediate. I have several other
postgres boxes 7.1.1 and there is no delay using this query, here is
what I'm getting with explain, but I don't know why?
notifydev=# explain select * from webfinal where w_artistkey = 'MICBUR'
order by w_date offset 2 limit 4;
NOTICE: QUERY PLAN:
Limit (cost=39.97..119.91 rows=4 width=109)
-> Index Scan using webfinal_w_date on webfinal
(cost=0.00..10563.49 rows=529 width=109)
EXPLAIN
notifydev=# explain select * from webfinal where w_artistkey = 'MICBUR'
order by w_date offset 2;
NOTICE: QUERY PLAN:
Limit (cost=999.97..999.97 rows=527 width=109)
-> Sort (cost=999.97..999.97 rows=529 width=109)
-> Index Scan using wf_ak1023165516 on webfinal
(cost=0.00..976.06 rows=529 width=109)
EXPLAIN
Now I run explain on a 7.1.3 box
news=# explain select * from webfinal where w_artistkey = 'MICBUR'
order by w_date offset 2 limit 4;
NOTICE: QUERY PLAN:
Limit (cost=924.71..924.71 rows=4 width=109)
-> Sort (cost=924.71..924.71 rows=498 width=109)
-> Index Scan using wf_ak1027580700 on webfinal
(cost=0.00..902.38 rows=498 width=109)
EXPLAIN
can someone explain this to me? Please send response directly as I am
not on the list.
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To: pgsql-sql@postgresql.org
Cc: Nathan@pollstar.com
Subject: Re: queries got slower using 7.1.3
In-Reply-To: <sd3fcb17.081@groupwise6.pollstar.com>
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