Performance of update statistics high
----LNX_Wed_Apr_28_2004_16:31:25_V3.33--
Content-Type: text/plain; charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
Hello everybody,
=
can anybody explain why 'update statistics high' should be run
seperately for the index columns?
=
Example:
table t (a,b,c,d) with composite indexes tx1 (a,b,c) and tx2 (a,b,d)
=
The recommendation is to run the following commands:
update statistics high for table t (a) ;
update statistics high for table t (c) ;
update statistics high for table t (d) ;=
Why should that be faster/better than running:
update statistics high for table t (a,c,d) ;=
Any comments appreciated.
=
Regards,
Andreas Kutsche
------------------------------------------------
SPAR Oesterreichische Warenhandels-AG
Hauptzentrale
Europastra=DFe 3
A-5015 Salzburg
=
Telefon : +43 662 4470 24423
E-Mail : Andreas.KUTSCHE@spar.at
Internet: http://www.spar.at
------------------------------------------------
=
----LNX_Wed_Apr_28_2004_16:31:25_V3.33----