Sorry for a vague post, but I have had this problem a couple of times & wondered whether anyone else has it & knows what causes it.

Very occasionally in my systems my DBISAM databases "lock up" ... it becomes impossible to open any table & there is an error #9272, basically something goes wrong with the DBISAM.lck file, which then blocks the opening of any table.

To "fix" the problem all that is needed is to delete the DBISAM.lck file or replace it with an empty text file with the name DBISAM.lck ... I have written a bit of code which does this in the case of this error ... but that seems like bad practice to me, I would like to know what might be causing the problem and what is actually wrong with the DBISAM.lck file when this happens.

Any ideas?

Adam


My antiquated version of DBISAM (4.25 I think) doesn't have error #9272 but the symptoms are similar to an old problem where the lock table actually filled up. That was to do with memory tables I was creating putting a lock entry in when I didn't want it. I think the "fix" was to set them to exclusive access but its a long time ago and I'm probably wrong anyway.

Roy Lambert [Team Elevate]

Thanks for the reply Roy.

>>DBISAM (4.25 I think) doesn't have error #9272

... might be #9217, I am communicating with the client via sms text's & the numbers they are sending aren't consistent!

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I guess it is possible that the lck file is getting overloaded, I don't know what size it is when the problem occurs. It might even be that protective programming I have added (to try to avoid data loss) is posting the records frequently & that might be causing the problem.

Adam

. might be #9217, I am communicating with the client via sms text's & the numbers they are sending aren't consistent!.

That would be nasty and also totally different.

>I guess it is possible that the lck file is getting overloaded, I don't know what size it is when the problem occurs. It might even be that protective programming I have added (to try to avoid data loss) is posting the records frequently & that might be causing the problem.

Its a long time back, especially with my ossifying brain cells but I seem to recall that the .lck file is a fixed size and can only hold a maximum number of entries which is where the problem came from.

As long as you stick with the same few physical tables that make up the database - no problem. I was creating and destroying memory tables all of which had a unique name. These were added to the .lck file and not removed. Eventually it filled up and any attempt to create a new memory table bombed.

Roy Lambert [Team Elevate]

Adam,

<< Very occasionally in my systems my DBISAM databases "lock up" ... it
becomes impossible to open any table & there is an error #9272, basically
something goes wrong with the DBISAM.lck file, which then blocks the opening
of any table. >>

As Roy indicated, that error code doesn't exist - was it 9217 or 9480,
perhaps ?  9480 is the error that you'll get if you "fill up" the lock file
per Roy's description.  A 9217 error indicates that something has corrupted
the .lck file and DBISAM can't read it's contents properly.  Is the
stability of the machine in question a bit sketchy ?  If so, then that could
cause this type of problem, especially if the application and data/lock file
are on the local drive of the machine.

--
Tim Young
Elevate Software
www.elevatesoft.com