Session vars of internal sql session not updated even user set global @sys_var

[guo-shaoge]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

1. Setup tidb cluster
2. Run the following sqls:

create table t(c1 int);
insert into t values(1), (2), (3);
set global sql_mode = 'NO_BACKSLASH_ESCAPES';

3. Restart tidb instance
4. Run

analyze table t;  // will give error because sql_mode
set global sql_mode = '';
// reconnect tidb and run
analyze table t;

2. What did you expect to see? (Required)

The last analyze should run ok.

3. What did you see instead (Required)

Still give parser error

4. What is your TiDB version? (Required)

+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| tidb_version()                                                                                                                                                                                                                                                                                        |
+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Release Version: v7.2.0-alpha-45-gda4bc2b905
Edition: Community
Git Commit Hash: da4bc2b9053b2842ce2bead531a0d4137286e75c
Git Branch: master
UTC Build Time: 2023-04-28 06:43:43
GoVersion: go1.20.1
Race Enabled: false
TiKV Min Version: 6.2.0-alpha
Check Table Before Drop: false
Store: unistore |
+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.001 sec)

[guo-shaoge]

Related parser error: #43392

[bb7133]

Close this issue(fixed by #43966).

For the SQL mode used by internal SQLs, we need to make it consolidated(tracked in #45604)