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Re: Query not using indexes

From: hastenthunder <hastenthunder_at_hotmail.com>
Date: Wed, 7 Jul 2004 19:14:15 -0400
Message-ID: <3s%Gc.578$Ny6.1570@mencken.net.nih.gov>

"Dave" <david.sharples3_at_ntlXworld.com> wrote in message news:9g0Hc.495$em4.332_at_newsfe3-gui.ntli.net...
>
> "hastenthunder" <hastenthunder_at_hotmail.com> wrote in message
> news:kj%Gc.577$Ny6.1552_at_mencken.net.nih.gov...
> >
> > "Dave" <david.sharples3_at_ntlXworld.com> wrote in message
> > news:C20Hc.476$em4.117_at_newsfe3-gui.ntli.net...
> > >
> > > "hastenthunder" <hastenthunder_at_hotmail.com> wrote in message
> > > news:vL_Gc.576$Ny6.1485_at_mencken.net.nih.gov...
> > > > Hi,
> > > >
> > > > A query of mine in Oracle 9i R2 chooses to perform a full table scan
> of
> > 1
> > > > million row instead of using the index.
> > > > I'm using CBO and just computed the statistics for the table.
> > > >
> > > > Can someone help?
> > > >
> > > > Thanks
> > > >
> > > >
> > >
> > > exec
> dbms_stats.gather_table_stats('SCHEMA_NAME','TABLE_NAME,casacde=true)
> > >
> > > are you sure a fts is a bad thing -
> > >
> > >
> >
> > Done that. Computed fresh statistics before sending the issue out via
> > analyze table command (its old, I know).
> > Just did it again using dbms_stats, still does not work...
> > Strange.., the query certainly access a substantial number of rows....
> >
> >
>
> if you are getting most of the rows back, fts is good
>
> see
>

http://asktom.oracle.com/pls/ask/f?p=4950:8:::::F4950_P8_DISPLAYID:4433887271030
>
>

Thanks Dave, you are right.
However, I'm only getting a single row back (out of 1 million).

SELECT fieldA
FROM tableA
WHERE fieldB = 'xxx'

And fieldB is indexed.
Seems like a very simple query, with fresh statistis. That's why this is puzzling me so much.... Received on Wed Jul 07 2004 - 18:14:15 CDT

Original text of this message

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