MySQL Bugs: #92638: Application "Not Responding" when deselecting a large number of rows.

Bug #92638	Application "Not Responding" when deselecting a large number of rows.
Submitted:	2 Oct 2018 15:55	Modified:	3 Oct 2018 10:09
Reporter:	Russell Bierschbach	Email Updates:
Status:	Verified	Impact on me:	None
Category:	MySQL Workbench: SQL Editor	Severity:	S5 (Performance)
Version:	8.0.2	OS:	Windows
Assigned to:		CPU Architecture:	x86

Description:
Application hangs (Not Responding) for a very long time after selecting/highlighting a large number of rows in the Result Grid.

How to repeat:
1) Execute a SELECT statement (SELECT * FROM largeTable LIMIT 25000);

The size of result set has a lot to do with the hang time. 10k rows with 5 columns is far worse than 20k rows with 1 column.

I suggest you work your way up from LIMIT 1000, 5000, etc, as the "Not Responding" time will get significantly longer with more rows, and there is no point in locking the app up for any longer than necessary to confirm the bug.

2) In the Result Grid, click the Top-Left corner to Select/Highlight all rows.

3) Click a cell in the Result Grid to deselect all rows.

Attempting to execute another query in the same window will also lock up the application for a while as Result Grid is reset.

4) Get coffee, lunch, or browse Reddit for a while.

5) MySQL workbench finally responds.

Thank you for the bug report.

https://bugs.mysql.com/bug.php?id=92682 marked as duplicate of this one.