'>= NULL' should not return the data

[aytrack]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

create table t3(a year);
insert into t3 values (1991), ("1992"), ("93"), (94);
select * from t3 where a >= NULL;

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

the result is empty.

mysql test> select * from t3 where a >= NULL;
+---+
| a |
+---+

3. What did you see instead (Required)

mysql test> create table t3(a year);
Query OK, 0 rows affected
Time: 0.255s
mysql test> insert into t3 values (1991), ("1992"), ("93"), (94);
Query OK, 4 rows affected
Time: 0.065s
mysql test> select * from t3 where a >= NULL;
+------+
| a    |
+------+
| 1991 |
| 1992 |
| 1993 |
| 1994 |
+------+
4 rows in set
Time: 0.056s
mysql root@172.16.4.131:test> desc select * from t3 where a >= NULL;
+---------------------+----------+-----------+---------------+--------------------------------+
| id                  | estRows  | task      | access object | operator info                  |
+---------------------+----------+-----------+---------------+--------------------------------+
| TableReader_7       | 3333.33  | root      |               | data:Selection_6               |
| └─Selection_6       | 3333.33  | cop[tikv] |               | ge(test.t3.a, 0)               |
|   └─TableFullScan_5 | 10000.00 | cop[tikv] | table:t3      | keep order:false, stats:pseudo |
+---------------------+----------+-----------+---------------+--------------------------------+

3 rows in set
Time: 0.064s

4. What is your TiDB version? (Required)

mysql root@172.16.4.131:test> select tidb_version()\G
***************************[ 1. row ]***************************
tidb_version() | Release Version: v4.0.0-beta.2-2135-gd6a2b9a37-dirty
Edition: Community
Git Commit Hash: d6a2b9a372edd3638c0ed88e1d2a5e6b702a69ed
Git Branch: master
UTC Build Time: 2021-02-11 02:48:59
GoVersion: go1.13
Race Enabled: false
TiKV Min Version: v3.0.0-60965b006877ca7234adaced7890d7b029ed1306
Check Table Before Drop: false

[lzmhhh123]

Caused by #21099

[ti-srebot]

Please edit this comment or add a new comment to complete the following information

Not a bug

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2. Add notes to indicate why it is not a bug

Duplicate bug

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2. Add the link to the original bug

Bug

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Example for how to fill out the template: #20100

1. Root Cause Analysis (RCA) (optional)

2. Symptom (optional)

3. All Trigger Conditions (optional)

4. Workaround (optional)

5. Affected versions

[v4.0.9:v4.0.11],[v5.0.0-rc]

6. Fixed versions

master

[seiya-annie]

[["21099"," expression: adjust int constant when compare with year type (#21099)\n"," v5.0.0-rc",null],
["21283"," expression: adjust int constant when compare with year type (#21099) (#21283)\n"," v4.0.9",null]]