Informix Transaction Logging

I have a question about transaction logging in Informix Dynamic Server 7.3 Our database is in unbuffered logging mode. When I issue an SQL command in dbaccess, such as "DELETE FROM table1", I soon get an SQL 458 error message - "Long Transaction aborted". There are about 50,000 rows in this table. I am not issuing a BEGIN WORK statement, so I am curious as to why transaction logging is still occuring. To make matters more confusing, we have another database instance (also in unbuffered logging mode) on our machine and when I issue a "DELETE FROM table1" command in dbaccess in the other instance, it works fine. The table in this other instance still has 50,000 rows in it. However, the transaction log files do not appear to be growing in size when issuing this command in the second instance. This is the behavior I would expect if I do not issue a BEGIN WORK statement. Can somebody shed some light on this as to why I may be getting this long transaction error message when I have not specified a BEGIN WORK statement? Thanks. - Mike Bloom mbloom@erols.com

Mike, There is a implicit 'command-level' begin work/commit work arround all statements. The only time that the implicet begin work is not done is when the user does an explicit begin work. If you are deleting rows from a logged table, then the before images of the row is placed into the log. This way the command can 'rollback' if the command is unsuccessful. As far as the other table goes - I don't know why you would not be seeing any logging. The only way that there should not be any logging would be if the database (or table) is not logged. If I were in your position, I'd cross-check about the other table that appears not to be logging. If you can verify that it is not logging, then I'd contact tech support as to why it is not. Mike Bloom wrote: > I have a question about transaction logging in Informix Dynamic Server > 7.3 Our database is in unbuffered logging mode. When I issue an SQL > command in dbaccess, such as "DELETE FROM table1", I soon get an SQL 458 > error message - "Long Transaction aborted". There are about 50,000 rows > in this table. I am not issuing a BEGIN WORK statement, so I am curious as > to why transaction logging is still occuring. > To make matters more confusing, we have another database instance (also > in unbuffered logging mode) on our machine and when I issue a "DELETE FROM > table1" command in dbaccess in the other instance, it works fine. The table > in this other instance still has 50,000 rows in it. However, the > transaction log files do not appear to be growing in size when issuing this > command in the second instance. This is the behavior I would expect if I do > not issue a BEGIN WORK statement. > Can somebody shed some light on this as to why I may be getting this > long transaction error message when I have not specified a BEGIN WORK > statement? Thanks. > > - Mike Bloom > mbloom@erols.com