RE: explain plan is changing ...

From: Christopher Spence <cspence_at_FuelSpot.com>
Date: Thu, 13 Sep 2001 11:18:35 -0700
Message-ID: <F001.0038DA44.20010913110838@fatcity.com>

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You probably have histograms, and very skewed data.

"Do not criticize someone until you walked a mile in their shoes, that way when you criticize them, you are a mile a way and have their shoes."

Christopher R. Spence
Oracle DBA
Phone: (978) 322-5744
Fax: (707) 885-2275

Fuelspot
73 Princeton Street
North, Chelmsford 01863  

-----Original Message-----
Sent: Thursday, September 13, 2001 2:11 PM To: Multiple recipients of list ORACLE-L

!! Please do not post Off Topic to this List !!

Hi all:

I have a query, which behaves differently depending on the input data (month/year). I have more than 15month worth of data in the database. The query is completed under 1 minute for the first 13 month, but for the last two months it just doesn't finish. I have cancelled it after 36 minutes. The explain plans are
differ in that the "quick" query uses more hash jonts, while "slow" one utilizes more nested loops. All the tables are analyzed. This must have something to do with the data distribution, but what? Can anyone shed some light onto that?

tia

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Author: Christopher Spence
  INET: cspence_at_FuelSpot.com

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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). Received on Thu Sep 13 2001 - 13:18:35 CDT