incorrectly fetch null data

[mahjonp]

Description

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. What did you do?

TiDB

mysql> create table t0(c0 int);
Query OK, 0 rows affected (0.07 sec)

mysql>  insert into t0 values(null);
Query OK, 1 row affected (0.01 sec)

mysql>  select * from t0 where ((!(1.5071004017670217e-01=t0.c0))) IS NULL;
Empty set (0.00 sec)

mysql> select ((!(1.5071004017670217e-01=null))) IS NULL;
+--------------------------------------------+
| ((!(1.5071004017670217e-01=null))) IS NULL |
+--------------------------------------------+
|                                          1 |
+--------------------------------------------+
1 row in set (0.00 sec)

TiDB and MySQL 8.0.19

4. What version of TiDB are you using? (tidb-server -V or run select tidb_version(); on TiDB)

mysql> select tidb_version();
+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| tidb_version()                                                                                                                                                                                                                                                                                         |
+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Release Version: v4.0.0-beta.2-305-g94011e6064
Git Commit Hash: 94011e6064fffc7df1057e2a9b2b866f429e7494
Git Branch: HEAD
UTC Build Time: 2020-04-21 11:03:51
GoVersion: go1.13.4
Race Enabled: false
TiKV Min Version: v3.0.0-60965b006877ca7234adaced7890d7b029ed1306
Check Table Before Drop: false |
+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)

SIG slack channel

#sig-exec

Score

• 300

Mentor

• @XuHuaiyu

[TszKitLo40]

/pick-up

[ti-challenge-bot]

Pick up success.

[TszKitLo40]

/give-up

[ti-challenge-bot]

Give up success.

[TszKitLo40]

/pick-up

[ti-challenge-bot]

Pick up success.

[ti-challenge-bot]

@TszKitLo40 You did not submit PR within 7 days, so give up automatically.

[TszKitLo40]

/pick-up

[ti-challenge-bot]

Pick up success.

[wshwsh12]

fixed by #24049

[ti-srebot]

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