tidb_mdl_view is not showing blocked ddl when ddl contains multiple table

[D3Hunter]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

• create 2 table, t1, t2, insert 1 row to them.
• in session 1:

begin;
select * from t1;

• in session 2, the sql will block

rename table t1 to t11, t2 to t22;

now query block

mysql> select * from mysql.tidb_mdl_view;
Empty set (0.02 sec)

it's because we're not put all table id into ddl_jobs view as ActionMultiSchemaChange do:

tidb/pkg/executor/executor.go

Line 492 in 3ef01b5

if job.Type == model.ActionMultiSchemaChange {

query using this sql, we can see the block, 122 is the table id of t1:

mysql> SELECT job_id,
    ->     json_extract(cast(cast(job_meta as char) as json), '$.schema_name') as db_name,
    ->     json_extract(cast(cast(job_meta as char) as json), '$.table_name') as table_name,
    ->     json_extract(cast(cast(job_meta as char) as json), '$.query') as query,
    ->     session_id,
    ->     txnstart,
    ->     tidb_decode_sql_digests(all_sql_digests, 4096) AS SQL_DIGESTS
    ->   FROM mysql.tidb_ddl_job,
    ->     information_schema.cluster_tidb_trx,
    ->     information_schema.cluster_processlist
    ->   WHERE tidb_ddl_job.processing = 1 and Find_in_set(122, tidb_ddl_job.table_ids)
    ->     AND Find_in_set(122, cluster_tidb_trx.related_table_ids)
    ->     AND cluster_tidb_trx.session_id = cluster_processlist.id;
+--------+---------+------------+-------------------------------------+------------+----------------------------------------+--------------------------------+
| job_id | db_name | table_name | query                               | session_id | txnstart                               | SQL_DIGESTS                    |
+--------+---------+------------+-------------------------------------+------------+----------------------------------------+--------------------------------+
|    126 | "test"  | "t2"       | "rename table t1 to t11, t2 to t22" | 1103101964 | 10-18 14:46:58.547(445018700132384769) | ["begin","select * from `t1`"] |
+--------+---------+------------+-------------------------------------+------------+----------------------------------------+--------------------------------+

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

3. What did you see instead (Required)

4. What is your TiDB version? (Required)

v7.4.0