executor: fix get var expr when session var is hex literal (#23241)

[ti-srebot]

cherry-pick #23241 to release-4.0
You can switch your code base to this Pull Request by using git-extras:

# In tidb repo:
git pr https://github.com/pingcap/tidb/pull/23372

After apply modifications, you can push your change to this PR via:

git push [email protected]:ti-srebot/tidb.git pr/23372:release-4.0-2890a8f62c32

---

Signed-off-by: guo-shaoge [email protected]

What problem does this PR solve?

Issue Number: close #22949

Problem Summary:

use test;
DROP TABLE IF EXISTS `IDT_MC10146`;
CREATE TABLE `IDT_MC10146` (
  `COL1` bit(4) DEFAULT NULL,
  `COL2` bit(4) DEFAULT NULL,
  `COL3` bit(4) DEFAULT NULL,
  KEY `U_M_COL` (`COL1`,`COL2`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin;
INSERT INTO `IDT_MC10146` VALUES (0x0F, 0x00, 0x08);
prepare stmt from 'select * from IDT_MC10146 where col1 in (?);';
set @a=0x3135;
execute stmt using@a;

GetVar expr(@sess_var) return string type when session_var is hex literal(eg: @sess_var = 0x3135), which is converted to '15'. Actually we should return BinaryLiteral type, but we dont have BinaryLiteral eval type.

What is changed and how it works?

What's Changed:

1. When UsingVar is GetVar expr and this session var is BinaryLiteral, we convert the result of GetVar (string) back to BinaryLiteral.
2. Before rewrite IN expr to EQ expr, check if contain mutalbe variables.

Related changes

• Need to cherry-pick to the release branch

Check List

Tests

• Integration test: expression.TestGetVarExprWithHexLiteral()

• Side effects: no

Release note

• fix get var expr when session var is hex literal

[ti-srebot]

/run-all-tests

[ti-srebot]

@guo-shaoge you're already a collaborator in bot's repo.

[guo-shaoge]

@lzmhhh123 @XuHuaiyu PTAL

[XuHuaiyu]

/lgtm

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• XuHuaiyu
• lzmhhh123

To complete the pull request process, please ask the reviewers in the list to review by filling /cc @reviewer in the comment.
After your PR has acquired the required number of LGTMs, you can assign this pull request to the committer in the list by filling /assign @committer in the comment to help you merge this pull request.

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

Reviewer can indicate their review by writing /lgtm in a comment.
Reviewer can cancel approval by writing /lgtm cancel in a comment.

[zhouqiang-cl]

/label cherry-pick-approved

[ti-chi-bot]

@zhouqiang-cl: The label(s) cherry-pick-approved cannot be applied. These labels are supported: CHANGELOG, challenge-program, compatibility-breaker, contribution, correctness, first-time-contributor, good-first-issue, hacktoberfest, high-performance, hptc, need-more-info, needs-cherry-pick-3.0, needs-cherry-pick-3.1, needs-cherry-pick-4.0, needs-cherry-pick-5.0-rc, needs-cherry-pick-5.0, proposal, release-note, require-LGT3, security, tools.

In response to this:

/label cherry-pick-approved

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 ti-community-infra/tichi repository.

[zhouqiang-cl]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: 265313e

[zhouqiang-cl]

/run-unit-tests