Repeatedly updating the same row will cause the stats_healthy to become low and generate wrong query plan

[King-Dylan]

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Repeatedly updating the same row will cause the stats_healthy to become low, which affects the correctness of the execution plan

1. Minimal reproduce step (Required)

mysql> create table t(a int);
mysql> insert into t values(1),(1),(1),(1),(1),(1),(1),(1);
Query OK, 8 row affected (0.01 sec)
mysql> show stats_meta where table_name='t';
+---------+------------+----------------+---------------------+--------------+-----------+
| Db_name | Table_name | Partition_name | Update_time         | Modify_count | Row_count |
+---------+------------+----------------+---------------------+--------------+-----------+
| test    | t          |                | 2023-10-10 16:36:50 |            0 |         8 |
+---------+------------+----------------+---------------------+--------------+-----------+
1 row in set (0.00 sec)
mysql> update t set a=2 where a=1 limit 1;
Query OK, 1 row affected (0.01 sec)
Rows matched: 1  Changed: 1  Warnings: 
mysql> update t set a=3 where a=2 limit 1;
Query OK, 1 row affected (0.00 sec)
Rows matched: 1  Changed: 1  Warnings: 0
mysql> select * from t;
+------+
| a    |
+------+
|    3 |
|    1 |
|    1 |
|    1 |
|    1 |
|    1 |
|    1 |
|    1 |
+------+
8 rows in set (0.00 sec)

mysql> update t set a=4 where a=3 limit 1;
Query OK, 1 row affected (0.01 sec)
Rows matched: 1  Changed: 1  Warnings: 0

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

mysql> show stats_meta where table_name='t';
+---------+------------+----------------+---------------------+--------------+-----------+
| Db_name | Table_name | Partition_name | Update_time         | Modify_count | Row_count |
+---------+------------+----------------+---------------------+--------------+-----------+
| test    | t          |                | 2023-10-10 16:40:47 |            1 |         8 |
+---------+------------+----------------+---------------------+--------------+-----------+
1 row in set (0.00 sec)

mysql> show stats_healthy where table_name='t';
+---------+------------+----------------+---------+
| Db_name | Table_name | Partition_name | Healthy |
+---------+------------+----------------+---------+
| test    | t          |                |      88 |
+---------+------------+----------------+---------+
1 row in set (0.00 sec)

3. What did you see instead (Required)

mysql> show stats_meta where table_name='t';
+---------+------------+----------------+---------------------+--------------+-----------+
| Db_name | Table_name | Partition_name | Update_time         | Modify_count | Row_count |
+---------+------------+----------------+---------------------+--------------+-----------+
| test    | t          |                | 2023-10-10 16:40:47 |            3 |         8 |
+---------+------------+----------------+---------------------+--------------+-----------+
1 row in set (0.00 sec)

mysql> show stats_healthy where table_name='t';
+---------+------------+----------------+---------+
| Db_name | Table_name | Partition_name | Healthy |
+---------+------------+----------------+---------+
| test    | t          |                |      12 |
+---------+------------+----------------+---------+
1 row in set (0.00 sec)

4. What is your TiDB version? (Required)

v6.5.3