Re: Upgrade of locks
No. And thank goodness for that. From: Henry Benoit <Benoit.Henry@Galvalange.lu> > >I've got a question about upgrade of locks. >Can informix upgrade a lock and promote at a higher level. > >For example : I have a table with 200,000 records and i do >an update for the entire table. The lock mode is row. >Can Informix detect that the process is locking about 100,000 rows >and react and say "ok guy, you already locked 100,000 record, > I'll give you a lock on the entire table, so I can release 99,999 locks >!" > >Thanks in advance > >Ben > ________________________________________________________________________ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com
Why do you say that? (the 'thank goodness for that' part.) It kinda sounded like a good idea... Of course, the overhead of unlocking all those rows would be cumbersome... In article <8h2se4$s93$1@news.xmission.com>, "Obnoxio The Clown" <obnoxio@hotmail.com> wrote: > > No. And thank goodness for that. > > From: Henry Benoit <Benoit.Henry@Galvalange.lu> > > > >I've got a question about upgrade of locks. > >Can informix upgrade a lock and promote at a higher level. > > > >For example : I have a table with 200,000 records and i do > >an update for the entire table. The lock mode is row. > >Can Informix detect that the process is locking about 100,000 rows > >and react and say "ok guy, you already locked 100,000 record, > > I'll give you a lock on the entire table, so I can release 99,999 locks > >!" > > > >Thanks in advance > > > >Ben > > > > ________________________________________________________________________ > Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com > > -- # unrm / ksh: unrm: not found # man cpio Sent via Deja.com http://www.deja.com/ Before you buy.
mars1972@my-deja.com wrote: > > Why do you say that? (the 'thank goodness for that' part.) It kinda > sounded like a good idea... A lot of things sound like good ideas until you work out all of the ramifications. Promotable locking causes more grief than it prevents. If a row lock were to promote to a table lock after say 80% of the rows had been locked other updaters would be locked out EVEN if the original process only needed to update 81% of the rows. If you know that you will be updating a large percentage of the rows in a table and you can afford to lock other users out of the table until the updates are complete then just LOCK TABLE <tabname> IN EXCLUSIVE MODE; Art S. Kagel > Of course, the overhead of unlocking all those rows would be > cumbersome... > > In article <8h2se4$s93$1@news.xmission.com>, > "Obnoxio The Clown" <obnoxio@hotmail.com> wrote: > > > > No. And thank goodness for that. > > > > From: Henry Benoit <Benoit.Henry@Galvalange.lu> > > > > > >I've got a question about upgrade of locks. > > >Can informix upgrade a lock and promote at a higher level. > > > > > >For example : I have a table with 200,000 records and i do > > >an update for the entire table. The lock mode is row. > > >Can Informix detect that the process is locking about 100,000 rows > > >and react and say "ok guy, you already locked 100,000 record, > > > I'll give you a lock on the entire table, so I can release 99,999 > locks > > >!" > > > > > >Thanks in advance > > > > > >Ben > > > > > > > > ________________________________________________________________________ > > Get Your Private, Free E-mail from MSN Hotmail at > http://www.hotmail.com > > > > > > -- > # unrm / > ksh: unrm: not found > # man cpio > > Sent via Deja.com http://www.deja.com/ > Before you buy.