Re: question about indexing.

Creager, Robert S <creagrs@louisville.stortek.com>

From: "Creager, Robert S" <CreagRS@LOUISVILLE.STORTEK.COM>
To: "'Doug McNaught'" <doug@wireboard.com>
Cc: pgsql-general@postgresql.org
Date: 2001-10-01T18:57:52Z
Lists: pgsql-general
Hey Doug,

Hmmm...  I just re-did two columns in a table from float4 from float8 'cause
the index was never used when executing a query.  I'm guessing that the
values from the select were used as a float8 then?  Thanks for the hint.

Later,
Rob


> -----Original Message-----
> From: Doug McNaught [mailto:doug@wireboard.com]
> Sent: Sunday, September 30, 2001 7:36 PM
> To: Brian Hirt
> Cc: pgsql-general@postgresql.org; Brian A Hirt
> Subject: Re: [GENERAL] question about indexing.
> 
> 
> "Brian Hirt" <bhirt@mobygames.com> writes:
> 
> > I have a table with about 1 million rows in it.  One of the 
> columns in this
> > table is some sort of status (it's an int2).  Out of the 
> million rows, only
> > about 100 of the rows have a status that is not like the rest.
> 
> > Yes, i do vacuum the table.
> > 
> > Does anyone know how to avoid all these table scans?
> 
> Cast the value you're testing against in the query to int2 
> and you may 
> see an improvement.  The planner isn't currently smart enough to
> realize it can use the index when the test value in the query is an
> int4.
> 
> -Doug
> -- 
> In a world of steel-eyed death, and men who are fighting to be warm,
> Come in, she said, I'll give you shelter from the storm.    -Dylan
> 
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