statistics: fix Clone method to include checked field in ColAndIdxExistenceMap

[Rustin170506]

What problem does this PR solve?

Issue Number: close #60104

Problem Summary:

What changed and how does it work?

We should also clone the checked field. Otherwise, the sync load will mistakenly attempt to load the stats of a non-existent index.

Note: This bug only occurs when there are no further writes to the table. Otherwise, the stats item is correctly updated as checked, preventing this issue from happening.

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.

None

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 73.8824%. Comparing base (7b81ae6) to head (d118e34).
Report is 7 commits behind head on master.

Additional details and impacted files

@@               Coverage Diff                @@
##             master     #60171        +/-   ##
================================================
+ Coverage   73.1557%   73.8824%   +0.7266%     
================================================
  Files          1708       1738        +30     
  Lines        471636     480570      +8934     
================================================
+ Hits         345029     355057     +10028     
+ Misses       105420     103596      -1824     
- Partials      21187      21917       +730     

Flag	Coverage Δ
integration	45.5732% <100.0000%> (?)
unit	72.4348% <100.0000%> (+0.0659%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
dumpling	52.6910% <ø> (ø)
parser	∅ <ø> (∅)
br	47.2537% <ø> (+0.0194%)	⬆️

🚀 New features to boost your workflow:

• ❄ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[Rustin170506]

/retest

[Rustin170506]

🔢 Self-check (PR reviewed by myself and ready for feedback.)

[Rustin170506]

Tested locally:

1. Start the TiDB cluster with patch: tiup playground v8.5.1 --db.binpath /Users/rustin/code/tidb/bin/tidb-server
2. Run queries:

USE test;
CREATE TABLE t1 (a INT, b INT, c INT);
CREATE TABLE t2 (a INT, b INT, c INT);
CREATE TABLE t3 (a INT, b INT, c INT);
CREATE TABLE t4 (a INT, b INT, c INT);

INSERT INTO t1 VALUES (1,3,0), (2,2,0), (3,2,0);
INSERT INTO t2 VALUES (3,3,0), (4,2,0), (5,3,0);
INSERT INTO t3 VALUES (1,2,0), (2,2,0);
INSERT INTO t4 VALUES (3,2,0), (4,2,0);

-- Wait for stats to be fully loaded
SHOW STATS_META;

CREATE INDEX idx_b ON t2(b);

SELECT t2.a, t2.b, t3.a, t3.b, t4.a, t4.b
  FROM (t3, t4)
       LEFT JOIN
       (t1, t2)
       ON t3.a = 1 AND t3.b = t2.b AND t2.b = t4.b
  ORDER BY 1, 2, 3, 4, 5;

3. Start a new TiDB(I use a debug instance):

USE test;
SELECT t2.a, t2.b, t3.a, t3.b, t4.a, t4.b
  FROM (t3, t4)
       LEFT JOIN
       (t1, t2)
       ON t3.a = 1 AND t3.b = t2.b AND t2.b = t4.b
  ORDER BY 1, 2, 3, 4, 5;

4. Check the logs, there are no warnings at all.

[Rustin170506]

/retest

Pull Request Overview

This pull request fixes the Clone method in the ColAndIdxExistenceMap by including the checked field, which prevents the sync load from attempting to load stats for a non-existent index.

• Added a test in table_test.go to validate the complete cloning behavior.
• Updated the Clone method in table.go to copy the checked field along with the analyzed maps.

Reviewed Changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated no comments.

File	Description
pkg/statistics/table.go	Clone method now includes the checked field
pkg/statistics/table_test.go	Added test to validate Clone method copying all fields

Files not reviewed (1)

• pkg/statistics/BUILD.bazel: Language not supported

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: hawkingrei, lance6716

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:

• pkg/statistics/OWNERS [hawkingrei]

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

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2025-03-20 01:56:31.725118661 +0000 UTC m=+493485.409354756: ☑️ agreed by lance6716.
• 2025-03-20 08:01:18.002841525 +0000 UTC m=+515371.687077607: ☑️ agreed by hawkingrei.

[Rustin170506]

/retest