On Tue, 12 Mar 2002, John Kanagaraj wrote: > I believe Jeremiah Wilton presented on a similar topic at OOW.
I did do a similar presenatation, and Rachel Carmichael did a similar one the year before. Also, Gaja has a tuning myths paper/presentation. Robert, you are welcome to consult my paper in doing your work. Just don't forget to correctly attribute material you use. http://www.speakeasy.net/~jwilton/oracle > One thing I will note though - there's bound to be lots of fire and > flak erupting in your presentation. There are *lots* of so-called > experienced DataBase Baby Sitters out there fed exclusively on > 'Oracle for Dummies' books who had adopted these myths as reality > and will be prepared to defend their position. You will need > documented evidence in the form of logs or timings to make your > stand for exploding some of these myths. There wasn't much flak in my presentation, just mostly good questions. But I was pretty keyed up, and some people might have just thought I was deranged and wanted to avoid provoking me :-/ -- Jeremiah Wilton http://www.speakeasy.net/~jwilton > >I'm doing Oracle Urban > > Legends. I've got > > several in my presentation but I thought I'd ask here, before > > I put the > > presentation to bed, what your favorite (or the one you find the most > > irritating) Oracle Urban legend was.... > > Robert, > > > * You *have* to take a COLD backup of the database after using resetlogs. > (Not required - a Hot backup and archive logs is adequate. All hot backups / > archive logs prior to that are invalid, though...) > * You *have* to create an additional Rollback segment in the SYSTEM > tablespace before creating *any* object in a tablespace other than SYSTEM > (even additional Rbs in a non-SYSTEM tablespace). This used to be true in V6 > and before, not anymore. > * Backup the online redologs along with the datafiles/controlfiles in a Hot > backup (Disaster strikes when the redologs are restored on the current > online redo logs!!) > * Continuously run ALTER TABLESPACE COALESCE > * Allocate different values of INITIAL/NEXT extent sizes for large objects > depending on the 'expected growth pattern' - this makes sure that the number > of extents for large objects is kept down. (Sheesh!) > * COMPRESS=Y during Export compresses the extents into 1 huge extent, and > that's GOOD! > * Make sure that all your Tablespaces have at least 15% (or whatever) free > (i.e. stress the percentage rather than making sure that the largest free > fragment is larger than the largest NEXT extent at the least) > * You are absolutely protected from Redolog file corruption by hardware > multiplexing it. (i.e. What if you fat-fingered an online redolog?) > > I might have added more on Tuning and Performance, but Gaja has already > exploded all those myths! > > > I am sure that others would add to this! (and I note that the 'lots of > extents is bad' myth is already noted!) > > John Kanagaraj > Oracle Applications DBA > DBSoft Inc > (W): 408-970-7002 > > Grace - Getting something we don't deserve > Mercy - NOT getting something we deserve > > Click on 'http://www.needhim.org' for Grace and Mercy that is freely > available! > > ** The opinions and statements above are entirely my own and not those of my > employer or clients ** > -- > Please see the official ORACLE-L FAQ: http://www.orafaq.com > -- > Author: John Kanagaraj > INET: [EMAIL PROTECTED] > > 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: [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.com -- Author: Jeremiah Wilton INET: [EMAIL PROTECTED] 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: [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).
