MySQL Bugs: #80054: Program hangs while running certain queries

Bug #80054	Program hangs while running certain queries
Submitted:	19 Jan 2016 17:44	Modified:	24 Sep 2016 6:16
Reporter:	Bill Lugo	Email Updates:
Status:	No Feedback	Impact on me:	None
Category:	MySQL Workbench	Severity:	S5 (Performance)
Version:	6.3.5	OS:	Windows (Microsoft Windows 7 Enterprise Service Pack 1)
Assigned to:		CPU Architecture:	Any
Tags:	WBBugReporter

Description:
----[For better reports, please attach the log file after submitting. You can find it in C:\Users\BillLugo\AppData\Roaming\MySQL\Workbench\log\wb.log]

Running queries sometimes causes Workbench to go on an infinite loop. It seems to happen to specific tables, but don't know what the criteria would be. Perhaps it's the amount of data, even though it'll happen with Limit 10. 

How to repeat:
Query specific tables.

Suggested fix:
If it's about pulling too much data, change the response to a warning dialog box with a yes/no option. Better yet, a progress indicator with a cancel option, so that we know that it's working and not frozen.

Using an older version (5.2 CE) helped as a bandaid. Perhaps it has something to do with a newer way in how it handles queries?

Here's a log excerpt (with some minor changes to names for security purposes):

12:30:38 [INF][        WQE.net]: Launching SQL IDE
12:30:39 [INF][        WQE.net]: SQL IDE UI is ready
12:30:41 [ERR][SqlEditorSchemaTree]: Exception querying metadata from mysql.proc, will fallback to SHOW PROCEDURE: Exception: SELECT command denied to user '-------'@'----.----.---' for table '----'
12:30:52 [ERR][      SqlEditor]: Error querying performance_schema.events_statements_current
: Exception: SELECT command denied to user '--------'@'----.----.---' for table 'events_statements_current'
12:30:52 [ERR][      SqlEditor]: Error querying performance_schema.event_stages_history
: Exception: SELECT command denied to user ''--------'@'----.----.---' for table 'events_stages_history_long'
12:30:52 [ERR][      SqlEditor]: Error querying performance_schema.event_waits_history
: Exception: SELECT command denied to user '--------'@'----.----.---' for table 'events_waits_history_long'
12:36:47 [ERR][      SqlEditor]: Error querying performance_schema.events_statements_current
: Exception: SELECT command denied to user '--------'@'----.----.---' for table 'events_statements_current'
12:36:47 [ERR][      SqlEditor]: Error querying performance_schema.event_stages_history
: Exception: SELECT command denied to user '--------'@'----.----.---' for table 'events_stages_history_long'
12:36:47 [ERR][      SqlEditor]: Error querying performance_schema.event_waits_history
: Exception: SELECT command denied to user '--------'@'----.----.---' for table 'events_waits_history_long'
12:36:56 [ERR][      SqlEditor]: Error querying performance_schema.events_statements_current
: Exception: SELECT command denied to user '--------'@'----.----.---' for table 'events_statements_current'
12:36:56 [ERR][      SqlEditor]: Error querying performance_schema.event_stages_history
: Exception: SELECT command denied to user '--------'@'----.----.---' for table 'events_stages_history_long'
12:36:56 [ERR][      SqlEditor]: Error querying performance_schema.event_waits_history
: Exception: SELECT command denied to user '--------'@'----.----.---' for table 'events_waits_history_long'

Please try version 6.3.6. Thanks.

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".

Tried version 6.3.6, problem still occurs. It does however seem to happen less often. 

-Task Manager needed to stop it
-a table that it always crashes on has the following specs:
--98 columns
---17 of them are varchar(255), 23 are varchar(100), 5 text, rest are small
--table size (est.): 2.9 MiB
--AVG row length: 363
-problem doesn't reproduce consistently with same limit (it occurred with limit 200, did not repeat after restarting with same limit)
--lower limits worked after restart. However, it hung again on limit 300.
--after another restart, worked on lower limits but hangs on limit 200 again

Using 6.3.7 now and the big query-handling has improved somewhat.

Seems like the bandaid was for the dev's to allow a bigger space for the query. However, I think it also needs:
1. the space limit to be expanded further (assuming that's how it works)
2. whatever the limit is, have some handling in place to catch bigger-than-its-limit queries, like a transaction cancellation option (the Stop Query button doesn't do it).

Anyway, I definitely appreciate the improvement.

Hello Bill Lugo,

Thank you for the bug report.
Could you please send us full stack trace to confirm this issue at our end?
steps to get stack trace:

# Microsoft Windows - Please make sure WB path is adjusted per installation.
C> cd "C:\Program Files (x86)\MySQL\MySQL Workbench CE 6.3.7\"
..> MySQLWorkbench.exe -log-level=debug3

Thanks,
Chiranjeevi

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".