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- Path: sparky!uunet!wupost!spool.mu.edu!agate!ucbvax!mtxinu!sybase!ben
- From: ben@sybase.com (Benjamin von Ullrich)
- Newsgroups: comp.databases.sybase
- Subject: Re: Recovering from a log segment full condition (don't set model's truncate log on checkpoint!)
- Message-ID: <27462@sybase.sybase.com>
- Date: 26 Dec 92 15:35:53 GMT
- References: <1992Dec22.173634.4259@sunova.ssc.gov> <VO!K2YHW3@linac.fnal.gov>
- Sender: news@Sybase.COM
- Organization: sybase, inc., emeryville-across-from-SF, ca
- Lines: 27
-
- i can give you a very good reason not to turn on the database option
- 'truncate log on checkpoint' on the model database. since this database is the
- template for all databases at CREATE DATABASE time, setting this option on
- model makes it be automatically set on all new databases as they are created.
- aside from the simple fact that this may not be what you want on all new
- databases, if you are in the midst of a frenzied recovery of a major production
- database (say, in the middle of the day, while all your users are down), and
- you load your database backup, the first gift your clever option on model will
- give you is a truncated log in front of all the transaction log dumps you were
- about to apply to bring the database you just loaded up to the time of failure.
- truncating the log at any time between LOAD DATABASE and your last LOAD
- TRANSACTION blasts a hole in the log chain and halts the recovery operation
- then & there.
-
- getting "out of sequence" errors from LOAD TRANSACTION while your boss
- and users are staring you down is NO FUN, and causes you unneeded embarassment
- when you call tech support for help because you KNOW you're "in sequence."
-
- avoid this potentially aggrivating situation and don't set truncate log on
- checkpoint on model. upgrade your sql server to 4.8 or 4.9.1 , and get
- this and many other problems fixed.
-
- --
- ..ben
- ------
- Benjamin von Ullrich only i do the talking here -- not my employer.
- ben@sybase.com {pyramid,pacbell,sun,lll-tis}!sybase!ben
-