MySQL Bugs: #78852: MySQL Workbench Defaults to REPEATABLE-READ regardlessly of server setting

Bug #78852	MySQL Workbench Defaults to REPEATABLE-READ regardlessly of server setting
Submitted:	16 Oct 2015 0:48	Modified:	12 Sep 2019 15:00
Reporter:	Yaning Zhu	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Workbench	Severity:	S3 (Non-critical)
Version:	6.3, 6.3.4	OS:	Any
Assigned to:		CPU Architecture:	Any
Tags:	ISOLATION, read, repeatable, transaction

Description:
Workbench ignores the tx_isolation setting on the server. It always defaults to REPEATABLE-READ. 

Need an option to allow Workbench to connect using server's setting by default.

How to repeat:
Connect to any MySQL instance.

`show session variables like '%tx%'` will always show REPEATABLE-READ.

Suggested fix:
Add an option in the preferences menu to allow us to specify isolation level.

Or let us modify a default .cnf file for Workbench.

Hello Yaning Zhu,

Thank you for the report.

Thanks,
Umesh

This just caused an outage that was fun to diagnose when an SE was using workbench without our knowledge.  This is a very serious degradation.  Please raise the severity, as workbench is basically useless on any enterprise system without a fix.

Hi, MySQL bug support team, We have met the same issue in 

MySQL Version: MySQL 5.6.26 
MySQL workbench Version: 6.3 CE.

Reprodure:
Step1: check the my.cnf files to confirm the transaction isolation was setting as Read-committed.
Step2: open one connection in MySQL workbench
Step3: Go to audit log and check what has been done:
I have found: the SQLTEXT like below, the line3 updated the isolation:
SET NAMES utf8
set autocommit=1
SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ
SET CHARACTER SET utf8
SET NAMES utf8
Step3: Check the session level transaction isolation.
it retruned REPEATABLE-READ.
show session variables like 'tx_isolation';

Step4: check other applicaitons, I have checked by MySQL client for linux, Toad for MySQL, Sqlyog, all shows with correct value: show session variables like 'tx_isolation'; as Read-committed.

What we have done: 
1. We tried to modify the file from installnation file: modules/opts.py for the transaction-isolation, we changed the default value to READ-COMMITTED, and restart the MySQL Workbench, but it not helped.
then we tried to remove the setting for the transaction_isolation and innodb_api_trx_level line and  it not helped either.

2. We tried to find somesettings on MySQL workbench GUI, but nothing related to the isolation setttings.

Please help to identify the root cause and provide a solution or ETA for fixing. Thanks.

I have met the same issue in

MySQL Version: MySQL 8.0.15 
MySQL workbench Version: 8.0.15

-----------------------------------
[general.log]

2019-06-19T07:30:38.670862Z        13 Connect   root@192.168.56.1 on  using SSL/TLS
2019-06-19T07:30:38.671133Z        13 Query     set autocommit=1
2019-06-19T07:30:38.671299Z        13 Query     SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ
2019-06-19T07:30:38.671556Z        13 Query     SHOW SESSION VARIABLES LIKE 'lower_case_table_names'
2019-06-19T07:30:38.675055Z        13 Query     SELECT current_user()
2019-06-19T07:30:38.675507Z        13 Query     SET CHARACTER SET utf8
2019-06-19T07:30:38.675780Z        13 Query     SET NAMES utf8
2019-06-19T07:30:38.676041Z        13 Query     SHOW SESSION VARIABLES LIKE 'sql_mode'
2019-06-19T07:30:38.679150Z        13 Query     SELECT CONNECTION_ID()
<<snip>>
-----------------------------------

Posted by developer:
 
This seems to be set by the c++ connector.

Posted by developer:
 
Fixed in 1.1.14, 8.0.19.

Connector/C++ set the transaction isolation level to REPEATABLE READ
at connect time, regardless of the current server setting.

Hi, I have found new update under this ticket:
https://bugs.mysql.com/bug.php?id=78852

But it says, this only fixed in 8.0 Version. How about the 6.2 and 6.3 Verison?

You can merge these 3 tickets as one ticket.
Bug no:
#69800
#86880
#78852

Looking forward offical reply.