[Bug] sql_select_limit for INSERT behaves different on master/non-master fe

[dh-cloud]

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• I had searched in the issues and found no similar issues.

Version

2.1.10

What's Wrong?

sql_select_limit for INSERT..SELECT/CREATE TABLE AS SELECT behaves different on master/non-master fe.

On master fe, sql_select_limit can affect the number of inserted rows.
On non-master fe, sql_select_limit does not affect the number of inserted rows.

What You Expected?

No matter master fe or non-masterfe, sql_select_limit should have the same effect for INSERT..SELECT/CREATE TABLE AS SELECT.

How to Reproduce?

run SQLs:

create table test(id int);
insert into test values(1),(2),(3),(4),(5),(6);

create table test_new(id int);

set sql_select_limit=1;
select * from test;
insert into test_new select * from test;

On master:

mysql> set sql_select_limit=1;
Query OK, 0 rows affected (0.00 sec)
mysql> select * from test;
+------+
| id |
+------+
| 1 |
+------+
1 row in set (0.04 sec)
mysql> insert into test_new select * from test;
Query OK, 1 row affected (0.59 sec)
{'label':'label_fdfe0bf2ed284b79_95d186162027f898', 'status':'VISIBLE', 'txnId':'46'}

On non-master fe:

mysql> set sql_select_limit=1;
Query OK, 0 rows affected (0.00 sec)
mysql> select * from test;
+------+
| id |
+------+
| 1 |
+------+
1 row in set (0.04 sec)
mysql> insert into test_new select * from test;
Query OK, 6 rows affected (0.67 sec)
{'label':'label_58eb29f33a52411a_a1a2654648bffbe3', 'status':'VISIBLE', 'txnId':'38'}

Anything Else?

No response

Are you willing to submit PR?

• Yes I am willing to submit a PR!

Code of Conduct

• I agree to follow this project's Code of Conduct

[morrySnow]

sql_select_limit should not affect on DML, so this is a bug

[dh-cloud]

sql_select_limit should not affect on DML, so this is a bug

@morrySnow But docs/en/docs/advanced/variables.md says:

• sql_select_limit

  Used to limit return rows of select stmt, including select clause of insert stmt.

Does this doc need an update?

[dh-cloud]

sql_select_limit should not affect on DML, so this is a bug

@morrySnow If I use set global, now it behaves the same on master/non-master fe: both affect DML.