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Home -> Community -> Mailing Lists -> Oracle-L -> Re: Optimizer behavior
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Yes.
Is there a reason why you want to compute statistics? If you want more accurate stats than estimate gives you, try estimating a larger sample.
ANALYZE TABLE xyz ESTIMATE STATISTICS SAMPLE 49 PERCENT ;
or
ANALYZE TABLE xyz ESTIMATE STATISTICS SAMPLE 49 PERCENT FOR TABLE FOR ALL INDEXES FOR ALL INDEXED COLUMNS;
if you want histograms.
cemail_at_sprintmail.com wrote:
We have a database set to CHOOSE. Although we would like to run compute statistics weekly on a particular schema's tables, it takes too long. If we were to do compute statistics once per month and estimate statistics weekly, would that be efficient? When estimate statistics is done is it overriding all of the statistics from compute statistics?
-- Author: INET: cemail_at_sprintmail.com Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). --------------------------------- Do You Yahoo!? Send instant messages & get email alerts with Yahoo! Messenger. --0-1102520059-962994916=:1449 Content-Type: text/html; charset=us-asciiReceived on Fri Jul 07 2000 - 13:35:16 CDT
<P>Yes. </P>
<P>Is there a reason why you want to compute statistics? If you want more accurate stats than estimate gives you, try estimating a larger sample.</P>
<P>ANALYZE TABLE xyz ESTIMATE STATISTICS SAMPLE 49 PERCENT ;<BR>or<BR>ANALYZE TABLE xyz ESTIMATE STATISTICS SAMPLE 49 PERCENT FOR TABLE FOR ALL INDEXES FOR ALL INDEXED COLUMNS;<BR>if you want histograms.<BR></P>
<P> <B><I>cemail_at_sprintmail.com</I></B> wrote: <BR>
<BLOCKQUOTE style="BORDER-LEFT: #1010ff 2px solid; MARGIN-LEFT: 5px; PADDING-LEFT: 5px"><BR>We have a database set to CHOOSE. Although we would like to<BR>run compute statistics weekly on a particular schema's tables,<BR>it takes too long. If we were to do compute statistics once<BR>per month and estimate statistics weekly, would that be efficient?<BR>When estimate statistics is done is it overriding all of the<BR>statistics from compute statistics?<BR><BR>-----<BR>Sent using MailStart.com ( http://MailStart.Com/welcome.html )<BR>The FREE way to access your mailbox via any web browser, anywhere!<BR><BR>-- <BR>Author: <BR>INET: cemail@sprintmail.com<BR><BR>Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051<BR>San Diego, California -- Public Internet access / Mailing Lists<BR>--------------------------------------------------------------------<BR>To REMOVE yourself from this mailing list, send an E-Mail message<BR>to: ListGuru@fatcity.com (note EXACT spelling of 'Li!
stGuru') and in<BR>the message BODY, include a line containing: UNSUB ORACLE-L<BR>(or the name of mailing list you want to be removed from). You may<BR>also send the HELP command for other information (like subscribing).</BLOCKQUOTE><p><br><hr size=1><b>Do You Yahoo!?</b><br> Send instant messages & get email alerts with Yahoo! Messenger.
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