Incorrect results for where clause with decimal constant division

[yibin87]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

create table test.t (id int, value decimal(7,4), c1 int, c2 int);
insert into test.t values (1,1.9285,54,28), (1,1.9286,54,28);
select * from t where value = 54 / 28;

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

Empty set.
From mysql 8.0.30

3. What did you see instead (Required)

mysql> select * from t where value = 54 / 28;
+------+--------+------+------+
| id | value | c1 | c2 |
+------+--------+------+------+
| 1 | 1.9286 | 54 | 28 |
+------+--------+------+------+
1 row in set, 7 warnings (0.00 sec)

4. What is your TiDB version? (Required)

mysql> select tidb_version();
+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| tidb_version() |
+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Release Version: v7.1.0-alpha
Edition: Community
Git Commit Hash: cd33faf
Git Branch: heads/refs/tags/v7.1.0-alpha
UTC Build Time: 2023-04-19 14:25:20
GoVersion: go1.20.3
Race Enabled: false
TiKV Min Version: 6.2.0-alpha
Check Table Before Drop: false
Store: tikv |
+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)

[yibin87]

Tidb behaves correctly for v7.0. The behavior changed recently.