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Thomas Hagedorn - Database breakdown ??

Thomas Hagedorn - Database breakdown ??

by Arnold Pizer -
Number of replies: 0
inactiveTopicDatabase breakdown ?? topic started 8/31/2005; 5:44:00 PM
last post 9/1/2005; 9:20:38 PM
userThomas Hagedorn - Database breakdown ??  blueArrow
8/31/2005; 5:44:00 PM (reads: 475, responses: 4)
Hi Everyone,

Thanks for all the suggestions about the previous error I posted. Unfortunately, today the errors got worse.

We have seen the following:

1. Correct answers not receiving credit. 2. Problems disappearing from problem sets, both before and after they are attempted. 3. Problems being reported as being attempted 1 or 2 times before they are attempted for the first time.

The errors have gotten so pervasive that we have suspended Webwork in our courses. Hopefully, only temporarily.

We are running Webwork 2.1.3. Unfortunately, I currently do not know which database setup we are using (the computer support person set it up. When I find out, I will post it).

Any suggestions on whether this is a Webwork 2.1.3 error or a database error? Any suggestions on how to fix it. If it is a Webwork error, what version of Webwork should we replace it with?

Thanks in advance, Tom Hagedorn

ps. I have learned that we are using gdbm as our database.

pps. I just read Jeff's post$3569#3577

which seems to be similar to the "first" errors we saw yesterday. I'm guessing that Webwork 2.1.3 is incompatible with gdbm and either we need to use mySQL or reinstall an earlier version of Webwork. Does this seem correct?

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userMichael Gage - Re: Database breakdown ??  blueArrow
8/31/2005; 6:15:12 PM (reads: 538, responses: 0)
Your early reports are consistent with problems I've seen where the problem sets were created sometime ago (perhaps using earlier versions of some software) and some of the data is not initialized properly. I've also seen one case of this where the first problem in a set disappeared. Deleting and then reinstalling the problem to the set for the entire class fixed that particular problem.

I'm running 116 courses on, most of them using the sql_single database structure and all of them using the very latest webwork code from the CVS. While I can't guarantee zero bugs on the CVS, it seems at least reasonably stable, and that code base is by far the easiest for the rest of us to trouble shoot and update. It also means that any fixes can be made available to you almost instantaneously.

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userMichael Gage - Re: Database breakdown ??  blueArrow
8/31/2005; 7:02:02 PM (reads: 535, responses: 0)
I'm guessing that Webwork 2.1.3 is incompatible with gdbm and either we need to use mySQL or reinstall an earlier version of Webwork. Does this seem correct?

As far as I know you can still use gdbm with Webwork version 2.1.3. I've just finished converting a number of courses on from gdbm to sql_single, but they appeared to be running reasonably smoothly over the summer. Certainly they were running last spring semester without any problems.

On the other hand we are converting almost entirely to the sql_single database format so we have less and less direct experience with using gdbm. This is true of most of the other developers as well. I would plan to switch to mysql databases at some point.

What is true is that WW2.1.3 is will no longer work interchangeably with WW1.9, even when using the gdbm database. WW2.1.3 keeps much more data about the state of problems and sets and is more careful in checking that that data has been properly initialized and that the data is preserved. If you create problems sets using WW1.9 tools and then use them with WW2.1.3 you are very likely to get warning messages about undefined data at the very least. Perhaps more.

-- Mike

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userJeff Denny - Re: Database breakdown ??  blueArrow
9/1/2005; 11:31:01 AM (reads: 529, responses: 0)

Your problems sound very similar to ours here. Switching to sql has corrected these problems. There seemed to be an error in the gdbm database from the moment it was created, but that has not been the case at all with sql. Although we have not done a full updated to the CVS version yet, I think we should and will based on what Mike and John Jones have posted.

Hope that you can get things running. Folks here were fairly patient while we worked this out, but our students were starting to get freaked out.


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userThomas Hagedorn - Re: Database breakdown ??  blueArrow
9/1/2005; 9:20:38 PM (reads: 501, responses: 0)
Hi Folks,

I wanted to update you on our situation. Today, we installed mySQL and reinitialized our courses. So far, we aren't seeing the small errors that we had seen 2 days ago. Tomorrow, we're going to have a small class test the system. But so far, it appears to be working fine.

Thanks for all your suggestions, Tom

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