support show table partition regions

[crazycs520]

Signed-off-by: crazycs520 crazycs520@gmail.com

What problem does this PR solve?

As the title said.

here is an example:

mysql>show table t partition (p4) regions;
+-----------+----------------+----------------+-----------+-----------------+-------+------------+---------------+------------+----------------------+------------------+
| REGION_ID | START_KEY      | END_KEY        | LEADER_ID | LEADER_STORE_ID | PEERS | SCATTERING | WRITTEN_BYTES | READ_BYTES | APPROXIMATE_SIZE(MB) | APPROXIMATE_KEYS |
+-----------+----------------+----------------+-----------+-----------------+-------+------------+---------------+------------+----------------------+------------------+
| 1047      | t_154_r        | t_154_r_200000 | 1048      | 1               | 1048  | 0          | 0             | 0          | 1                    | 1                |
| 1049      | t_154_r_200000 | t_154_r_400000 | 1050      | 1               | 1050  | 0          | 0             | 0          | 1                    | 0                |
| 1051      | t_154_r_400000 | t_154_r_600000 | 1052      | 1               | 1052  | 0          | 0             | 0          | 1                    | 0                |
| 1053      | t_154_r_600000 | t_154_r_800000 | 1054      | 1               | 1054  | 0          | 0             | 0          | 1                    | 0                |
| 2         | t_154_r_800000 |                | 3         | 1               | 3     | 0          | 747           | 0          | 1                    | 0                |
| 1045      | t_154_         | t_154_r        | 1046      | 1               | 1046  | 0          | 0             | 0          | 1                    | 1                |
+-----------+----------------+----------------+-----------+-----------------+-------+------------+---------------+------------+----------------------+------------------+
6 rows in set
Time: 0.009s
mysql>show table t partition (p3) regions;
+-----------+-----------+---------+-----------+-----------------+-------+------------+---------------+------------+----------------------+------------------+
| REGION_ID | START_KEY | END_KEY | LEADER_ID | LEADER_STORE_ID | PEERS | SCATTERING | WRITTEN_BYTES | READ_BYTES | APPROXIMATE_SIZE(MB) | APPROXIMATE_KEYS |
+-----------+-----------+---------+-----------+-----------------+-------+------------+---------------+------------+----------------------+------------------+
| 1041      | t_153_    | t_154_  | 1042      | 1               | 1042  | 0          | 0             | 0          | 1                    | 0                |
+-----------+-----------+---------+-----------+-----------------+-------+------------+---------------+------------+----------------------+------------------+
1 row in set

What is changed and how it works?

Check List

Tests

• Unit test

Code changes

• Has exported function/method change

Side effects

• No

Related changes

• Need to cherry-pick to the release branch

[codecov]

Codecov Report

Merging #855 into master will increase coverage by 0.00%.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #855   +/-   ##
=======================================
  Coverage   78.28%   78.28%           
=======================================
  Files          40       40           
  Lines       14665    14667    +2     
=======================================
+ Hits        11480    11482    +2     
  Misses       2502     2502           
  Partials      683      683           

[kennytm]

LGTM

[crazycs520]

/rebuild

[tangenta]

LGTM

[crazycs520]

/run-all-tests