planner: support PointGet plan when table has alias name

[sduzh]

What problem does this PR solve?

fix #11149

What is changed and how it works?

Check List

Tests

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

Side effects

• Increased code complexity

Related changes

• Need to cherry-pick to the release branch
• Need to update the documentation
• Need to update the tidb-ansible repository
• Need to be included in the release note

manual tests

mysql> create table t (a int not null, b int not null, c char(50) not null, primary key(a, b));
Query OK, 0 rows affected (0.01 sec)
mysql> explain select * from t where a = 1 and b = 1;
+-------------+-------+------+--------------------+
| id | count | task | operator info |
+-------------+-------+------+--------------------+
| Point_Get_1 | 1.00 | root | table:t, index:a b |
+-------------+-------+------+--------------------+
1 row in set (0.00 sec)
mysql> explain select * from t tmp where a = 1 and b = 1;
+-------------+-------+------+--------------------+
| id | count | task | operator info |
+-------------+-------+------+--------------------+
| Point_Get_1 | 1.00 | root | table:t, index:a b |
+-------------+-------+------+--------------------+
1 row in set (0.00 sec)
mysql> select tmp.a, tmp.b, tmp.c from t tmp where t.a = 1 and t.b = 1;
ERROR 1054 (42S22): Unknown column 't.a' in 'where clause'
mysql> select tmp.a, tmp.b, tmp.c from t tmp where tmp.a = 1 and tmp.b = 1;
Empty set (0.01 sec)

[codecov]

Codecov Report

Merging #11270 into master will decrease coverage by 0.1285%.
The diff coverage is n/a.

@@               Coverage Diff                @@
##             master     #11270        +/-   ##
================================================
- Coverage   81.7927%   81.6642%   -0.1286%     
================================================
  Files           426        426                
  Lines         94380      93473       -907     
================================================
- Hits          77196      76334       -862     
- Misses        11785      11786         +1     
+ Partials       5399       5353        -46

[winoros]

@sduzh It should be planner instead of palnner.

[zz-jason]

LGTM

[sre-bot]

Hi contributor, thanks for your PR.

This patch needs to be approved by someone of admins. They should reply with "/ok-to-test" to accept this PR for running test automatically.

[eurekaka]

Please follow the comment convention, for example: comment starting with function name / variable name; capitalize first character of beginning word and add . in the end of sentences.

[sduzh]

done

[eurekaka]

LGTM

[eurekaka]

/run-all-tests

[sre-bot]

/run-all-tests