DDL: admin show next_row_id return empty set

[3pointer]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

1. set @@sql_mode="";
2. create table t(a int not null, time timestamp not null default '0000-00-00 00:00:00', primary key (a));
3. admin show t next_row_id;

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

something like that:
+---------+------------+-------------+--------------------+
| DB_NAME | TABLE_NAME | COLUMN_NAME | NEXT_GLOBAL_ROW_ID |
+---------+------------+-------------+--------------------+
| test | t | _tidb_rowid | 1 |
+---------+------------+-------------+--------------------+

3. What did you see instead (Required)

empty set

4. Affected version (Required)

TiDB master branch(v4.0.2 has no such problem)

5. Root Cause Analysis

[fzhedu]

/label component/DDL

[tangenta]

It is an expected behavior after #18326. I didn't realize this before. Sorry :)