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RE: Is this a performance issue?

From: Glenn Travis <Glenn.Travis_at_wcom.com>
Date: Tue, 25 Jul 2000 11:46:30 -0400
Message-Id: <10569.112892@fatcity.com>


Unless all columns can be satisfied with an index (but you already knew that, right?).

If you have are selecting 5 columns, and say, three of them make up an index, you may want to consider storing the other two in the index as dangling columns. Depending on your table size, joins to other tables, performance needs, this could be a real win...

> -----Original Message-----
> From: root_at_fatcity.com [mailto:root_at_fatcity.com]On Behalf Of
> Kamesh.J.Mantri_at_citicorp.com
> Sent: Tuesday, July 25, 2000 5:24 AM
> To: Multiple recipients of list ORACLE-L
> Subject: RE: Is this a performance issue?
>
>
> Actually this is not a performance issue bcos when Oracle fetches
> rows for a
> select it does in with implicit cursor
> which goes row by row not column by column. Even if we mention
> a single col
> it fetches the whole row.
>
> Gurus correct me I am wrong..
>
>
> Kamesh.
>
> -----Original Message-----
> Sent: Monday,July 24, 2000 9:07 PM
> To: ORACLE-L
> Cc: schanna
>
>
> Gurus,
>
> I'm wondering if it's a performance issue if i select all the
> columns from
> a table even if you don't require.
>
> Let say I have a table which has about 50 columns in it and i need to get
> values for only 5-10 columns. So, instead of selecting only these columns
> I select *.
>
> Any idea if that screws up my performance?
>
>
>
> Santhosh Babu
>
> --
> Author: Channa, Santhosh, SITS
> INET: schanna_at_att.com
>
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> --
> Author:
> INET: Kamesh.J.Mantri_at_citicorp.com
>
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Received on Tue Jul 25 2000 - 10:46:30 CDT

Original text of this message

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