Panic/wrong reuslt when using partition table.

[wshwsh12]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

drop table t;
CREATE TABLE `t` (
  `fid` bigint(36) NOT NULL,
  `oty` varchar(30) DEFAULT NULL,
  `oid` int(11) DEFAULT NULL,
  `pid` bigint(20) DEFAULT NULL,
  `bid` int(11) DEFAULT NULL,
  `r5` varchar(240) DEFAULT '',
  PRIMARY KEY (`fid`)
)PARTITION BY HASH( `fid` ) PARTITIONS 4;

INSERT INTO t (fid, oty, oid, pid, bid, r5) VALUES (59, 'm',  441, 1,  2143,  'LE1264_r5');
INSERT INTO t (fid, oty, oid, pid, bid, r5) VALUES (135, 'm',  1121, 1,  2423,  'LE2008_r5');
INSERT INTO t (fid, oty, oid, pid, bid, r5) VALUES (139, 'm',  1125, 1,  2432, 'LE2005_r5');
INSERT INTO t (fid, oty, oid, pid, bid, r5) VALUES (143, 'm',  1129, 1,  2438,  'LE2006_r5');
INSERT INTO t (fid, oty, oid, pid, bid, r5) VALUES (147, 'm',  1133, 1,  2446,  'LE2014_r5');
INSERT INTO t (fid, oty, oid, pid, bid, r5) VALUES (167, 'm',  1178, 1,  2512,  'LE2055_r5');
INSERT INTO t (fid, oty, oid, pid, bid, r5) VALUES (171, 'm',  1321, 1,  2542,  'LE1006_r5');
INSERT INTO t (fid, oty, oid, pid, bid, r5) VALUES (179, 'm',  1466, 1,  2648,  'LE2171_r5');
INSERT INTO t (fid, oty, oid, pid, bid, r5) VALUES (187, 'm',  1567, 1,  2690,  'LE1293_r5');
INSERT INTO t (fid, oty, oid, pid, bid, r5) VALUES (57, 'm',  341, 1,  2102,  'LE1001_r5');
INSERT INTO t (fid, oty, oid, pid, bid, r5) VALUES (137, 'm',  1123, 1,  2427,  'LE2003_r5');
INSERT INTO t (fid, oty, oid, pid, bid, r5) VALUES (145, 'm',  1131, 1,  2442,  'LE2048_r5');
INSERT INTO t (fid, oty, oid, pid, bid, r5) VALUES (138, 'm',  1124, 1,  2429,  'LE2004_r5');
INSERT INTO t (fid, oty, oid, pid, bid, r5) VALUES (142, 'm',  1128, 1,  2436,  'LE2049_r5');
INSERT INTO t (fid, oty, oid, pid, bid, r5) VALUES (174, 'm',  1381, 1,  2602,  'LE2170_r5');
INSERT INTO t (fid, oty, oid, pid, bid, r5) VALUES (28, 'm',  81, 1,  2023,  'LE1009_r5');
INSERT INTO t (fid, oty, oid, pid, bid, r5) VALUES (60, 'm',  442, 1,  2145,  'LE1263_r5');
INSERT INTO t (fid, oty, oid, pid, bid, r5) VALUES (136, 'm',  1122, 1,  2425,  'LE2002_r5');
INSERT INTO t (fid, oty, oid, pid, bid, r5) VALUES (140, 'm',  1126, 1,  2434,  'LE2001_r5');
INSERT INTO t (fid, oty, oid, pid, bid, r5) VALUES (168, 'm',  1179, 1,  2514,  'LE2052_r5');
INSERT INTO t (fid, oty, oid, pid, bid, r5) VALUES (196, 'm',  3380, 1,  2890,  'LE1300_r5');
INSERT INTO t (fid, oty, oid, pid, bid, r5) VALUES (208, 'm',  3861, 1,  3150,  'LE1323_r5');
INSERT INTO t (fid, oty, oid, pid, bid, r5) VALUES (432, 'm',  4060, 1,  3290,  'LE1327_r5');

SELECT DISTINCT t.bid, t.r5 FROM t left join t parent on parent.oid = t.pid WHERE t.oty = 'm'; 

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

MySQL [test]> SELECT DISTINCT t.bid, t.r5 FROM t left join t parent on parent.oid = t.pid WHERE t.oty = 'm'; 
+------+-----------+
| bid  | r5        |
+------+-----------+
| 2690 | LE1293_r5 |
| 2425 | LE2002_r5 |
| 2436 | LE2049_r5 |
| 2602 | LE2170_r5 |
| 2423 | LE2008_r5 |
| 2446 | LE2014_r5 |
| 2512 | LE2055_r5 |
| 3150 | LE1323_r5 |
| 2145 | LE1263_r5 |
| 2143 | LE1264_r5 |
| 2432 | LE2005_r5 |
| 2429 | LE2004_r5 |
| 2542 | LE1006_r5 |
| 2023 | LE1009_r5 |
| 3290 | LE1327_r5 |
| 2890 | LE1300_r5 |
| 2102 | LE1001_r5 |
| 2427 | LE2003_r5 |
| 2438 | LE2006_r5 |
| 2648 | LE2171_r5 |
| 2434 | LE2001_r5 |
| 2514 | LE2052_r5 |
| 2442 | LE2048_r5 |
+------+-----------+
23 rows in set (0.001 sec)

3. What did you see instead (Required)

in 4.0, it will get runtime error: index out of range [2] with length 2 ("runtime error: index out of range [2] with length 2")
in master, it will get wrong result.

4. What is your TiDB version? (Required)

[zz-jason]

how did you find this bug?

[wshwsh12]

how did you find this bug?

@zz-jason It's an OnCall issue...

[ti-srebot]

Please edit this 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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Bug

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Example for how to fill out the template: #20100

1. Root Cause Analysis (RCA)

When creating partition union, it uses shallow copy to copy the field Column. Two DataSource will write to the same address and make the data wrong.

2. Symptom

As the describe above. Panic or wrong result.

3. All Trigger Conditions

Using partition table. Using column pruning optimization.

4. Workaround (optional)

No.

5. Affected versions

[v4.0.7]

6. Fixed versions

[v4.0.8]

[ti-srebot]

(WorkAroud RCA AllTriggerConditions FixedVersions AffectedVersions Symptom ) fields are empty.

[seiya-annie]

sync sig label from PR