The opposite WHERE clause intersects and is always an empty set. It should perform no action.

## Bug Report

Dear TiDB Developer:

Since q1 and q2 have opposite WHERE clause (e.g., = and !=), q1 INTERSECT q2 should always produce empty set and without physical read.

q1: SELECT * FROM TABLES CROSS JOIN COLUMNS WHERE TABLES.TABLE_NAME != COLUMNS.TABLE_NAME
q2: SELECT * FROM TABLES CROSS JOIN COLUMNS WHERE TABLES.TABLE_NAME = COLUMNS.TABLE_NAME;

However, TiDB actually executed such an unnecessary query. I think such queries should be optimized.

Best regard,

### 1. Minimal reproduce step (Required)

```
mysql> use INFORMATION_SCHEMA;
mysql> SELECT * FROM TABLES CROSS JOIN COLUMNS WHERE TABLES.TABLE_NAME != COLUMNS.TABLE_NAME
INTERSECT
SELECT * FROM TABLES CROSS JOIN COLUMNS WHERE TABLES.TABLE_NAME = COLUMNS.TABLE_NAME;
Empty set (34.72 sec)
```
### 2. What did you expect to see? (Required)
```
mysql> SELECT * FROM TABLES CROSS JOIN COLUMNS WHERE TABLES.TABLE_NAME != COLUMNS.TABLE_NAME
INTERSECT
SELECT * FROM TABLES CROSS JOIN COLUMNS WHERE TABLES.TABLE_NAME = COLUMNS.TABLE_NAME;
Empty set (00.00 sec)
```
### 3. What did you see instead (Required)
```
mysql> SELECT * FROM TABLES CROSS JOIN COLUMNS WHERE TABLES.TABLE_NAME != COLUMNS.TABLE_NAME
INTERSECT
SELECT * FROM TABLES CROSS JOIN COLUMNS WHERE TABLES.TABLE_NAME = COLUMNS.TABLE_NAME;
Empty set (34.72 sec)
```
### 4. What is your TiDB version? (Required)
| Release Version: v8.5.1
Edition: Community
Git Commit Hash: https://github.com/pingcap/tidb/commit/fea86c8e35ad4a86a5e1160701f99493c2ee547c
Git Branch: HEAD
UTC Build Time: 2025-01-16 07:38:34
GoVersion: go1.23.4
Race Enabled: false
Check Table Before Drop: false
Store: tikv |