Larry is the SQL guru. Every time he drops a pearl of wisdom like "we really want to make sure all the not-null columns are identified because it can affect the ability of the optimizer to transform a corelated IN subquery into an equi-join, and allow us to drop this index now that we won't need it for a correlated lookup, which will force all of our queries to rip through this table using hash joins" I wonder how the heck he KNOWS all that stuff.
I THINK it is just pure brains, although sometimes I suspect he has a deal with the devil ... or Larry Ellison. :>) Jack > don't feel too sheepish, I didn't know it either. Larry is the SQL guru > and I bow to his knowledge. and had already saved off this email as > this sort of update is something we do often and I ALWAYS have problems > figuring out the correct SQL :) > > rachel > --- Jared Still <[EMAIL PROTECTED]> wrote: > > > > Geez, I didn't know you could do that. > > > > Sheepishly, > > > > Jared > > > > On Friday 27 December 2002 03:38, Larry Elkins wrote: > > > Someone asked in a back channel email if parallelism is used. The > > select > > > portion of the update statement uses parallelism (though the > > updates > > > themselves get serialized) through the use of an in-line join > > update (to > > > avoid the second sub-query commonly used to constrain the rows > > being > > > updated): > > > > > > Update (Select /*+ parallel hints */ .... > > > From a,b > > > Where a.key = b.key) > > > Set a.col1 = b.col1, > > > a.col2 = b.col2 > > > ..... > > > > > > Regards, > > > > > > Larry G. Elkins > > > [EMAIL PROTECTED] > > > 214.954.1781 > > > > > > > -----Original Message----- > > > > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of > > Larry > > > > Elkins > > > > Sent: Thursday, December 26, 2002 6:09 PM > > > > To: Multiple recipients of list ORACLE-L > > > > Subject: Row Migration > > > > > > > > > > > > Listers, > > > > > > > > 8.1.7.4 64 Bit Solaris > > > > > > > > Does row migration utilize DB File Sequential Reads on the table? > > Off the > > > > top of my head I would expect so, but I've never tested something > > > > like that > > > > before. > > -- > > Please see the official ORACLE-L FAQ: http://www.orafaq.net > > -- > > Author: Jared Still > > 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). > > > > > __________________________________________________ > Do you Yahoo!? > Yahoo! Mail Plus - Powerful. Affordable. Sign up now. > http://mailplus.yahoo.com > -- > Please see the official ORACLE-L FAQ: http://www.orafaq.net > -- > Author: Rachel Carmichael > 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). > > > Thanks, Jack Silvey -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Jack Silvey 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).
