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I have an application in VB6 which has been running on the same machine for years. The database shuts down over night and comes back on after an hour or two.
The application goes to sleep way before the database shut down and wakes up after the restart.
This past Monday, we came in to see the runtime 3709 error. No code was modified, no updates to the Oracle database.
Any idea what might be causing this? Thanks!
What's the error description?
3709 - The connection cannot be used to perform this operation. It is either closed or invalid in this context.
JudyKamber,
Exactly 10 years ago I used ASP (v2.0?) and wrote up a few ASP postings in the then freevbcode.com. My postings are still there, but I've not been able to find anything directly related. However, a quick web search shows up something which might be of relevance to your case, would you like to take a look (if you haven't)?
xxxx://bytes.com/topic/visual-basic-net/answers/626558-3709-error-ado-when-using-persistant-conenction
[Edit: I shouldn't have provided a full outside link, please change the first 4 letters]
Depending on how database back is done (hot or cold) all live connection may need to be killed so...Quote:
Originally Posted by JudyKamber
Check connection state and reconnect if necessary - that's pretty standard (and simple too) task.
Did the computer install system updates that day?
Thanks all for your input. I tried setting a few instances to nothing which should have been done anyway to free up resources but that didn't help. I checked with the DBAs to see if Oracle was upgraded and it wasn't. Now I'll check with the HelpDesk staff to see if any updates were applied on that machine. They always so no but I'll see if I can persuade someone to really check!
Keep those ideas coming; they're appreciated.
If you restart it and it does not hapeen again for 10 years forget about it :).
Funny. Unfortunately, it's happened every morning this week so restarting didn't help.
As RhinoBull suggested in #5 above. Check for closed connection and reconnect as needed. You can build a sub/function that tests the connection state & reconnects. In your routines that query the DB, add error handling, that will call that new function when an error occurs.
Out of curiosity, is this happening in the AM when the app is suppose to reconnect to Oracle, after it has already been connected, or sometime before the app goes to sleep?
Thanks, LaVolpe. We do have checks for connection and attempts to reconnect. And all the other background applications running on that machine have the same connect/reconnect logic and are fine. Very strange.
I'm going to have to put some debugging messages into the application to know when it's failing. I only know it's fine during the day when we're here and I'm not willing to stay overnight and wait for it to fail!
Don't blame you. That's where error trapping and logging to file comes in play. Hopefully, it will provide insight right away.Quote:
Originally Posted by JudyKamber
Edited: Don't forget to add date/time to your log entries!
While DAO was marginally acceptable to me, ADO is just rubbish - all kinds of bugs and instability, and the worse is so many drastical changes over the years.
How bad is ADO? if I have a choice, I am willing to pay $10 for something like the then Ashton Tetes' dBase, rather than to spend $1 on MS's ADO.
Am I qualified to say something about database? I guess I am (designatory letters after my name used to include "FCMA" of UK, Fellow of Chartered .....).
I used DAO for many years, and ADO for many years after that - and I have never thought that ADO had as many bugs as DAO, nor that it is less stable, nor that it has had any drastic changes over the years.
I don't know what experiences you have had, but you have come to a very different conclusion to the usual impressions I get from people.
... Accountants?Quote:
Am I qualified to say something about database, I guess I am (designatory letters after my name used to include "FCMA" of UK, Fellow of Chartered .....).