Sure. The original post mentioned 8.1.7.2! - Kirti
-----Original Message----- Sent: Tuesday, November 26, 2002 3:29 AM To: Multiple recipients of list ORACLE-L pdml on non-partitioned tables is there in 9i hth connor --- "Deshpande, Kirti" <[EMAIL PROTECTED]> wrote: > How true !! I just ignored the 'writing' part of the > parallelized 'reading'. Sorry. > Thanks for catching it, Waleed. > Our own update process, that I am baby sitting, was > on my mind that involves a few partitioned tables... > > > Regards, > > - Kirti > > -----Original Message----- > Sent: Monday, November 25, 2002 9:09 PM > To: Multiple recipients of list ORACLE-L > > > PDML can be used only on partitioned segments. When > PQO is used during an > update on a non-partitioned segment, the parallel > processes (slaves) work > together to scan (read) the segment and find the > rows that need to be > updated. these rows get communicated back to the > master process using the > rowid. The master process starts to update rows > serially using the rowid for > update and this process could be slow and resources > intensive specially when > you are updating most of the rows in the table (you > will see tons of db file > sequential read). > > Regards, > > Waleed > > -----Original Message----- > Sent: Monday, November 25, 2002 7:19 PM > To: Multiple recipients of list ORACLE-L > > > I would consider PDML to get the job done faster, > provided there are enough > resources. > Using a cursor seems like a good idea, but avoid > fetching across commits. We > are going through a similar exercise, adding > 10000000 to a cust_id field to > denote the source of the data, and Developers > complained about ORA-1555. > Asked them not to commit as existing rollback > segments and space were > adequate ;) > > Good Luck, > > - Kirti > > -----Original Message----- > Sent: Monday, November 25, 2002 3:04 PM > To: Multiple recipients of list ORACLE-L > > > I've got a real hot project (8.1.7.2 on HP/UX 11.0) > that needs to have NULLs > converted to spaces on three different columns. > Each is a CHAR, so I > shouldn't need to worry about chaining, since that > column's full size has > already been allocated in the block, right? But the > first column has 1.2M > NULLs out of 1.45M rows. > > My first test was to just UPDATE mytable SET mycol = > ' ' WHERE mycol IS > NULL, after removing the index on that column. > Seeing as there were many > more rows updated than I had anticipated, I was > going to test the UPDATE > using a cursor, and committing at every 10K rows > (~120 total commits) to > reduce rollback and locking issues. > > Thoughts? Since this table is used for > time-and-attendance and directly > affects payroll, downtime isn't possible. > > TIA! > > Rich > > > Rich Jesse System/Database > Administrator > [EMAIL PROTECTED] Quad/Tech > International, Sussex, WI USA > -- -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Deshpande, Kirti 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).
