I seem to be missing some of the replies etc to this so apologies for repeating anything anyone else has said.
1. A BCHR of x% means that you have a well tuned system (where x is usually > 95) 2. Minimise the number of extents for each object 3. Set PCTIncrease to a small value (typically 1%) to minimise fragmentation. 4. Index blocks never get reused. 5. Rebuild indexes frequently. 6. Separation of data and indexes improves performance 7. The most selective column of a concatenated index should be the leading Column 8. If its in print it must be true 9. If 'x' says so it must be true. 10. Avoid Full Table Scans, they are always bad. Niall > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of > Stephane Paquette > Sent: 01 April 2003 15:54 > To: Multiple recipients of list ORACLE-L > Subject: Oracle urban legends and myths needed > > > Hi all, > > I'm currently writing an Oracle user guide for our > developpers about how Oracle is implemented, SQL and PL/SQL > good practices, tuning, rule base vs cost base (90 on 120 > databases are still rule base) ... > > > I want to add an Oracle urban legends and myths section > focussed on development. I'm missing inspiration as I only > have the "use an index it'll go faster" one. > > I'm sure you have lots of them. > > > TIA > > Stephane Paquette > Administrateur de bases de donnees > Database Administrator > Standard Life > www.standardlife.ca > Tel. (514) 925-7187 > [EMAIL PROTECTED] > <mailto:[EMAIL PROTECTED]> > > > -- > Please see > the official ORACLE-L FAQ: http://www.orafaq.net > -- > Author: Stephane Paquette > INET: [EMAIL PROTECTED] > > Fat City Network Services -- 858-538-5051 http://www.fatcity.com > San Diego, California -- Mailing list and web hosting services > --------------------------------------------------------------------- > To REMOVE yourself from this mailing list, send an E-Mail message > to: [EMAIL PROTECTED] (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). > -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Niall Litchfield INET: [EMAIL PROTECTED] Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (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).