planner: fix choosing the partition wrongly when the where stmt is only one eq condition. (#16975)

[sre-bot]

cherry-pick #16975 to release-4.0

---

What problem does this PR solve?

Issue Number: close #16842

Problem Summary: Got wrong result because of choosing wrong partition

select /*+ HASH_JOIN(t1, t2) */ * from t1 partition (p0) left join t2 partition (p1) on t1.a = t2.a where t1.a = 6 order by t1.a, t1.b, t2.a, t2.b;
+--------------------------------+---------+---------+-----------+------------------------+----------------------------------------------------------------------------+------------------------------------------------------------+--------------+---------+
| id                             | estRows | actRows | task      | access object          | execution info                                                             | operator info                                              | memory       | disk    |
+--------------------------------+---------+---------+-----------+------------------------+----------------------------------------------------------------------------+------------------------------------------------------------+--------------+---------+
| Sort_9                         | 0.01    | 1       | root      |                        | time:417.345µs, loops:2                                                    | test.t1.a:asc, test.t1.b:asc, test.t2.a:asc, test.t2.b:asc | 1.4609375 KB | 0 Bytes |
| └─HashJoin_12                  | 0.01    | 1       | root      |                        | time:403.351µs, loops:2, Concurrency:5, probe collision:0, build:3.341µs   | CARTESIAN left outer join                                  | 16.46875 KB  | 0 Bytes |
|   ├─TableReader_19(Build)      | 0.00    | 1       | root      |                        | time:246.412µs, loops:2, rpc num: 1, rpc time:263.064µs, proc keys:0       | data:Selection_18                                          | 185 Bytes    | N/A     |
|   │ └─Selection_18             | 0.00    | 1       | cop[tikv] |                        | time:68.752µs, loops:2                                                     | eq(6, test.t2.a)                                           | N/A          | N/A     |
|   │   └─TableFullScan_17       | 2.00    | 2       | cop[tikv] | table:t2, partition:p6 | time:62.883µs, loops:3                                                     | keep order:false, stats:pseudo                             | N/A          | N/A     |
|   └─TableReader_16(Probe)      | 0.01    | 1       | root      |                        | time:337.02µs, loops:2, rpc num: 1, rpc time:360.723µs, proc keys:0        | data:Selection_15                                          | 185 Bytes    | N/A     |
|     └─Selection_15             | 0.01    | 1       | cop[tikv] |                        | time:177.32µs, loops:2                                                     | eq(test.t1.a, 6)                                           | N/A          | N/A     |
|       └─TableFullScan_14       | 9.00    | 9       | cop[tikv] | table:t1, partition:p0 | time:161.26µs, loops:10                                                    | keep order:false, stats:pseudo                             | N/A          | N/A     |
+--------------------------------+---------+---------+-----------+------------------------+----------------------------------------------------------------------------+------------------------------------------------------------+--------------+---------+
8 rows in set (0.00 sec)

The partition should be p1 instead of p6 for t2. (Of course, table dual is also ok.)

What is changed and how it works?

What's Changed: Check the datasource's partitions includes the partition build from condition.

How it Works:

+-------------------------------+---------+---------+-----------+------------------------+------------------------------------------------------------------------+------------------------------------------------------------+--------------+---------+
| id                            | estRows | actRows | task      | access object          | execution info                                                         | operator info                                              | memory       | disk    |
+-------------------------------+---------+---------+-----------+------------------------+------------------------------------------------------------------------+------------------------------------------------------------+--------------+---------+
| Sort_9                        | 0.01    | 1       | root      |                        | time:1.717822ms, loops:2                                               | test.t1.a:asc, test.t1.b:asc, test.t2.a:asc, test.t2.b:asc | 1.4609375 KB | 0 Bytes |
| └─HashJoin_12                 | 0.01    | 1       | root      |                        | time:1.686675ms, loops:2, Concurrency:5, probe collision:0, build:0s   | CARTESIAN left outer join                                  | 0 Bytes      | 0 Bytes |
|   ├─TableDual_17(Build)       | 0.00    | 0       | root      |                        | time:335.178µs, loops:1                                                | rows:0                                                     | N/A          | N/A     |
|   └─TableReader_16(Probe)     | 0.01    | 1       | root      |                        | time:1.574268ms, loops:2, rpc num: 1, rpc time:1.160928ms, proc keys:0 | data:Selection_15                                          | 185 Bytes    | N/A     |
|     └─Selection_15            | 0.01    | 1       | cop[tikv] |                        | time:316.313µs, loops:2                                                | eq(test.t1.a, 6)                                           | N/A          | N/A     |
|       └─TableFullScan_14      | 9.00    | 9       | cop[tikv] | table:t1, partition:p0 | time:286.938µs, loops:10                                               | keep order:false, stats:pseudo                             | N/A          | N/A     |
+-------------------------------+---------+---------+-----------+------------------------+------------------------------------------------------------------------+------------------------------------------------------------+--------------+---------+
6 rows in set (0.01 sec)

Related changes

• Need to cherry-pick to the release branch

Check List

Tests

• Unit test
• Integration test

Side effects

Release note

• Bug-fix: Fix choosing the partition wrongly when there is only one eq condition.

[sre-bot]

/run-all-tests

[imtbkcat]

LGTM

[wshwsh12]

/run-all-tests

[zz-jason]

LGTM

[sre-bot]

/run-all-tests