MySQL Bugs: #69613: Queries on a a tables with hundreds of columns hang, i.e.

Bug #69613	Queries on a a tables with hundreds of columns hang, i.e. > 580 columns
Submitted:	28 Jun 2013 16:31	Modified:	15 Jan 2014 19:12
Reporter:	George Dombrowski	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Workbench	Severity:	S2 (Serious)
Version:	6.0.2	OS:	MacOS (Version 10.8)
Assigned to:		CPU Architecture:	Any
Tags:	67717

Description:
I've reported this bug previously, #67717 and it still exists in the most recent version of the Workbench for Mac OS-X. It is so serious that I have to Force Quit Workbench in order to regain control. 

The problem occurs regardless of the engine used to construct the table. 

If I use the Windows based versions of Workbench all works just fine. Even using a third party, i.e. the DBSolo GUI, to work with my databases works fine.

How to repeat:
If necessary I can send you the create table statement with a few rows of fake data.

Suggested fix:
I'm thinking that perhaps it is a memory management problem, too small a buffer perhaps?

Please provide a sample CREATE statement and sample data that can produce the bug.

Create Table Statement- Will Try to Supply Random Data for Columns Later

Attachment: create_chaptest.sql (application/octet-stream, text), 11.73 KiB.

Have uploaded Create Table Statement and Will Try to Supply Random Column Data Later.

I was able to repeat. Seems to be a bug in Cocoa, since if disable resizing of the columns it goes back to being pretty fast. We'll see if we can workaround it.

Alfredo, thank you for working on this problem. It is good to know that I can disable the resizing of columns to work around the bug. If it is a Cocoa bug, perhaps using Numbers or Excel with a large spreadsheet would reproduce the error when you resize columns in those programs. I don't think I ever noticed such a problem with a large Excel spreadsheet, but I think that I have had some frustrating issues with slowness using Numbers, but I don't know if it would be related to the same postulated Cocoa bug.

Alfredo, I was just checking to see if this bug had been assigned. Thanks.

Alfredo, how do you disable resizing of the query output columns. I can't find the setting.

Thanks.

Apologies for long delay, we could only revisit the issue now.
The option to disable column resizing is in Cocoa, we did not have such an option in WB yet.
However, we've added a check for resultsets with many columns. In that case, a dialog will popup and ask whether you want to disable column resizing to workaround this problem. This workaround is currently not in version 6.0.x, but should become available soon.

As for the underlying Cocoa bug, Excel and certain other applications are not affected because they use a different method to display grids. We may implement something similar in the future, but since this is a corner case, it may take a while until that happens.

Fixed as of the upcoming Workbench 6.1.1 release, and here is the changelog entry:

On Mac OS X, an option to "Disable column Resizing" or continue is now
displayed when a query is determined to display too many columns. This
works around a Cocoa issue that could potentially freeze MySQL Workbench.

Thank you for the bug report.