planner: make var_samp can be used as a window function (#53130)

[ti-chi-bot]

This is an automated cherry-pick of #53130

What problem does this PR solve?

Issue Number: close #52933

Problem Summary:

What changed and how does it work?

From the MySQL plan:

mysql> explain analyze select var_samp(c1) over (partition by c1) from t1;
+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| EXPLAIN                                                                                                                                                                                                                                                                                                                |
+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| -> Window aggregate with buffering: var_samp(t1.c1) OVER (PARTITION BY t1.c1 )   (cost=0 rows=1) (actual time=0.139..0.139 rows=0 loops=1)
    -> Sort: t1.c1  (cost=0.35 rows=1) (actual time=0.133..0.133 rows=0 loops=1)
        -> Table scan on t1  (cost=0.35 rows=1) (actual time=0.116..0.116 rows=0 loops=1)
 |
+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.01 sec)

• Made var_samp can be used as a window function.
• Added a test case for use var_samp as window function cause unexpected error #52933.

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No need to test

  • I checked and no code files have been changed.

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

Make `var_samp` can be used as a window function.
使 `var_samp` 可以用作窗口函数。

[ti-chi-bot]

@ti-chi-bot: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
idc-jenkins-ci-tidb/build	a0ee23f	link	true	/test build
idc-jenkins-ci-tidb/unit-test	a0ee23f	link	true	/test unit-test
idc-jenkins-ci-tidb/check_dev	a0ee23f	link	true	/test check-dev

Full PR test history. Your PR dashboard.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository. I understand the commands that are listed here.

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-05-16 02:52:20.383773615 +0000 UTC m=+1708094.140909173: ☑️ agreed by tangenta.

[easonn7]

/approve

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: easonn7, tangenta

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [tangenta]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment