executor: add missing update table delta for TxnCtx

[blacktear23]

What problem does this PR solve?

Issue Number: close #20975

Problem Summary:

mysql> drop table t2, t1;
Query OK, 0 rows affected (0.04 sec)

mysql> create table t1(a int);
Query OK, 0 rows affected (0.01 sec)

mysql> insert into t1 values (1);
Query OK, 1 row affected (0.00 sec)

mysql> begin pessimistic;
Query OK, 0 rows affected (0.00 sec)

mysql> update t1 set a=a;
Query OK, 0 rows affected (0.00 sec)
Rows matched: 1  Changed: 0  Warnings: 0

/* session 2 */ mysql> create table t2(a int);
Query OK, 0 rows affected (0.00 sec)

mysql> commit;
ERROR 8028 (HY000): Information schema is changed during the execution of the statement(for example, table definition may be updated by other DDL ran in parallel). If you see this error often, try increasing `tidb_max_delta_schema_count`. [try again later]

What is changed and how it works?

What's Changed:

When update statement without changes it missing track table ID for SchemaValidator. So when execute commit statement will cause SchemaValidator check whole Schema without tables and this will cause schema change error.

Related changes

• No

Check List

Tests

• Manual test (steps see below)

mysql> drop table t2, t1;
Query OK, 0 rows affected (0.04 sec)

mysql> create table t1(a int);
Query OK, 0 rows affected (0.01 sec)

mysql> insert into t1 values (1);
Query OK, 1 row affected (0.00 sec)

mysql> begin pessimistic;
Query OK, 0 rows affected (0.00 sec)

mysql> update t1 set a=a;
Query OK, 0 rows affected (0.00 sec)
Rows matched: 1  Changed: 0  Warnings: 0

/* session 2 */ mysql> create table t2(a int);
Query OK, 0 rows affected (0.00 sec)

mysql> commit;
Query OK, 0 rows affected (0.00 sec)

Side effects

• Performance regression
  • Consumes more CPU when DML cause nothing changes
  • Consumes more MEM when DML cause nothing changes
  • Add lock for update TableDeltaMap may cause little slower

Release note

• No Release Note

[blacktear23]

@cfzjywxk PTAL

[bb7133]

PTAL @cfzjywxk

[cfzjywxk]

LGTM

[lysu]

LGTM

[lysu]

/merge

[ti-srebot]

/run-all-tests

[ti-srebot]

@blacktear23 merge failed.

[wjhuang2016]

LGTM

[lysu]

/merge

[ti-srebot]

Your auto merge job has been accepted, waiting for:

• 21015

[blacktear23]

/run-tics-test

[jebter]

@wjhuang2016 Maybe cherry-pick to the 4.0 branch?

[wjhuang2016]

/run-cherry-picker

[ti-srebot]

cherry pick to release-4.0 in PR #21279