slow update but have an index - Mailing list pgsql-general

From Feite Brekeveld
Subject slow update but have an index
Date
Msg-id 3B7CFB2D.6418E7E5@osiris-it.nl
Whole thread Raw
Responses Re: slow update but have an index  (Martijn van Oosterhout <kleptog@svana.org>)
Re: slow update but have an index  (Tom Lane <tgl@sss.pgh.pa.us>)
Re: slow update but have an index  (Tod McQuillin <devin@spamcop.net>)
List pgsql-general
Hi,

I have a table with no relations to other tables. It has a sequence
number field (integer) and a status field being a char.

There is a unique index on the seqno field.

Now this table has about 80,000 records. I need to update 74,000 status
fields. So I made a dump, and hacked the dump into SQL statements like:

update accounting set status = 'C' where seqno = 1566385;
....
and the other 74,000



This is awfully slow. How come ? The index on the seqno should give
speedy access to the record.

Thanks,

--
Feite Brekeveld
feite.brekeveld@osiris-it.nl
http://www.osiris-it.nl




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