MySQL Bugs: #84688: Ban change sql

Bug #84688	Ban change sql_mode on session level
Submitted:	26 Jan 2017 19:52
Reporter:	Aleksey Filippov	Email Updates:
Status:	Open	Impact on me:	None
Category:	MySQL Server: General	Severity:	S4 (Feature request)
Version:	5.7	OS:	Any
Assigned to:		CPU Architecture:	Any
Tags:	ban, session variables

Description:
Global variable sql_mode set to STRICT_ALL_TABLES(mysqld.cnf).
But someone changes this variable on session level, and from time to time we have problem with data in our database.
And there is no ability to ban changing sql_mode on session level.
It could be good decision to have some mysqld.cnf parameter(global variable) than allow to ban changing sql_mode on session level.
Actually, great decision is to have ability to ban setting session variables listed in some global variable.

How to repeat:
set global sql_mode to STRICT_ALL_TABLES.
connect to mysql.
set session sql_mode to other value.
now you can damage data inside database.

See also: http://mysqlserverteam.com/feedback-request-enforcing-sql-mode/