util: Fix lock view cannot show key info correctly for partition table (#27027)

[ti-srebot]

cherry-pick #27027 to release-5.2
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/27035

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

git push [email protected]:ti-srebot/tidb.git pr/27035:release-5.2-e539f9d62f87

---

What problem does this PR solve?

Problem Summary: Currently when using the data_lock_waits and deadlocks table of lock view, if it shows a key from a partitioned table, the key_info column may not show the key's information correctly. It's because Lock View didn't handle these kind of keys correctly. This PR fixes this problem.

What is changed and how it works?

Proposal: xxx

What's Changed: In util/keydecoder, which is specifically used by Lock View for finding information from keys: When failed to find a table by table ID, try to use it as a partition ID and try to find the partition info and its corresponding table info.

Check List

Tests

• Unit test
• Manual test (add detailed scripts or steps below)

/* init */ drop table if exists t;
-- init >> 0 rows affected
/* init */ create table t (id int primary key, uk int, v int, unique key i1 (uk, id)) partition by range (id) ( partition p0 values less than (10), partition p1 values less than maxvalue);
-- init >> 0 rows affected
/* init */ insert into t values (1, 1, 1), (2, 2, 2);
-- init >> 2 rows affected
/* t1:wait */ begin;
-- t1 >> 0 rows affected
/* t1 */ update t set v = v + 1 where id = 1;
-- t1 >> 1 rows affected
/* t2 */ begin;
-- t2 >> 0 rows affected
/* t2 */ update t set v = v + 1 where id = 1;
-- t2 >> blocked
/* t4 */ select * from information_schema.data_lock_waits;
-- t4 >> +----------------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------+--------------------+------------------------+------------------------------------------------------------------+-----------------------------------------------+
-- t4    |                  KEY                   |                                                                  KEY INFO                                                                  |       TRX ID       | CURRENT HOLDING TRX ID |                            SQL DIGEST                            |                SQL DIGEST TEXT                |
-- t4    +----------------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------+--------------------+------------------------+------------------------------------------------------------------+-----------------------------------------------+
-- t4    | 74800000000000004D5F728000000000000001 | {"db_id":1,"db_name":"test","table_id":76,"table_name":"t","partition_id":77,"partition_name":"p0","handle_type":"int","handle_value":"1"} | 426901898605101059 |     426901898605101057 | 06da614b93e62713bd282d4685fc5b88d688337f36e88fe55871726ce0eb80d7 | update `t` set `v` = `v` + ? where `id` = ? ; |
-- t4    +----------------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------+--------------------+------------------------+------------------------------------------------------------------+-----------------------------------------------+
/* t1 */ rollback;
-- t1 >> 0 rows affected
-- t2 >> resumed
-- t2 >> 1 rows affected

Side effects

• None

Documentation

• None

Release note

None

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• cfzjywxk
• youjiali1995

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[ti-srebot]

/run-all-tests

[ti-srebot]

@MyonKeminta you're already a collaborator in bot's repo.

[cfzjywxk]

/merge

[ti-chi-bot]

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

Commit hash: 32a7b1e

[youjiali1995]

/merge