Issue 33724

Summary: MySQL does not stop two processes/users overwriting each others changes in a record
Product: Base Reporter: kelvine <kelvineld>
Component: codeAssignee: AOO issues mailing list <issues>
Status: CONFIRMED --- QA Contact:
Severity: Trivial    
Priority: P3 CC: issues
Version: OOo 1.1.2   
Target Milestone: ---   
Hardware: All   
OS: All   
Issue Type: ENHANCEMENT Latest Confirmation in: ---
Developer Difficulty: ---

Description kelvine 2004-09-02 03:19:35 UTC
Hi,

This may be more of an enhancement request than a defect. Please change if 
appropriate.

I thought record locking for MySQL would be handled at the server end, but I 
find I can overwrite data when two processes are accessing the same record.

By this I mean I start to change the contents of a field in a record using a 
Form. Then using the data source window I edit the same field in the same 
record and save the changes whilst the data in the Form is still open.

When the changes from the Form are saved this overwrites the changes from the 
data source window without warning.

Using MS Access as a front end a warning is provided and the user who attempts 
to save second is stopped. The MS Access approach is far from ideal but at 
least the user is warned.

To duplicate this perform the following.

Open a Form which displays a record in a table in a MySQL database.
Click in a text field and start to change the contents
Don't leave the field at this stage.

Now open a second view of the data as follows
Press F4 to open the data source window
Open the same MySQL table as the above form is using
Locate the same record being edited above
Change the field that you started to change to something else
Now complete the change by moving to another record

Finally return to the form and complete the change
Move to another record or manually save the record.

What happens is the second change overwrites the first change without warning.

This creates the situation where one process or user, can destroy changes 
performed by another process or user.

Is there perhaps a setting that needs to be enabled in MySQL?

Is this simply a limitation of OO that it doesn't handle record locking 
situations.

If it is a limitation of OO, then please convert this to an enhancement 
request to add record locking features.

Thanks

Kelvin
Comment 1 marc.neumann 2004-09-29 09:13:47 UTC
Hi,

yes I can reproduce this.

I change the type to enhancement.

And reassign this to User Experience for evaluating the record locking feature.

Bye Marc
Comment 2 bettina.haberer 2010-05-21 15:14:52 UTC
To grep the issues easier via "requirements" I put the issues currently lying on
my owner to the owner "requirements".