Bug #19692 portions of updates lost with no error message received

• Submitted: 10 May 2006 17:13
• Modified: 14 Jun 2006 15:23
• Reporter: Scott Richardson
• Status: No Feedback
• Category: Connector / NET
• Severity: S2 (Serious)
• Version: 1.0.7
• OS: Linux (Red Hat E3)
• CPU Architecture: Any

[10 May 2006 17:13] Scott Richardson

Description:
With a .Net 1.1 VS2003 program issueing sets of updates to databaes on exit across the internet using the data adapter update method the following things were occurring:

1) The connections kept dropping/aborting. Compression had to be turned off in order to keep connection up long enough to update/insert anything.
Number of connections up to about 200. updates are in try/catch block.
2) Then intermittently, but repeatably occurring, "some" of the updates where lost as confirmed by looking at the update log and seeing (for instance) the insert command for one record, but not the insert command for a record before or after that. No error was received back to the client and no rows where marked as in 'error' in the datatable in question.
3) Lost data seemed to cluster around one or two days a week and was more frequent at customers using the product in higher latency environment with more updates occurring. In a very low latency environment i could never reproduce it. 
4) Other products using the datbase in a smiliar manner but using the MyODBC driver did not appear to have the same problem.

How to repeat:
Uncertain but the following elements are part of it:

1) 200 connections
2) multiple connections from one program on multiple threads
3) multiple data adapaters
4) innodb tables
5) other products hitting database using myodbc
6) high latency connection
7) updating on exit from program
8) early updates/inserts lost as oppossed to later ones i.e. i lost the first or third update/insert and never the last update/insert though take this one with a grain of salt
9) commpression had to be turned off

Suggested fix:
After opening/closing the connection before every single update and upgrading the database to version 5.0.19, the error has now occurred only once in a one month period.

[10 May 2006 17:21] Scott Richardson

Using the .net connection 1.07

[14 May 2006 15:23] Valeriy Kravchuk

Thank you for a problem report. Please, upload you my.cnf content. Try also to repeat with a newer version of server, 5.0.21. Can you repeat this problem each and every time with specific UPDATE/table?

[14 Jun 2006 23:00] Bugs System

No feedback was provided for this bug for over a month, so it is
being suspended automatically. If you are able to provide the
information that was originally requested, please do so and change
the status of the bug back to "Open".