infoschema: Add SERVER_CONNECT_ATTRS table

[dveeden]

What problem does this PR solve?

Issue Number: close #44341

Problem Summary:

What is changed and how it works?

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

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.

Connection Attributes can now be queried via the `INFORMATION_SCHEMA.SESSION_CONNECT_ATTRS` table.

[ti-chi-bot]

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[ti-chi-bot]

Skipping CI for Draft Pull Request.
If you want CI signal for your change, please convert it to an actual PR.
You can still manually trigger a test run with /test all

[dveeden]

TiDB, with this PR:

sql> SELECT * FROM information_schema.SESSION_CONNECT_ATTRS;
+----------------+-----------------+------------+------------------+
| PROCESSLIST_ID | ATTR_NAME       | ATTR_VALUE | ORDINAL_POSITION |
+----------------+-----------------+------------+------------------+
|  2199023255955 | _client_name    | libmysql   |                0 |
|  2199023255955 | _client_version | 8.0.33     |                1 |
|  2199023255955 | _os             | Linux      |                2 |
|  2199023255955 | _pid            | 712927     |                3 |
|  2199023255955 | _platform       | x86_64     |                4 |
|  2199023255955 | program_name    | mysqlsh    |                5 |
+----------------+-----------------+------------+------------------+
6 rows in set (0.0012 sec)

MySQL 8.0.33

sql> SELECT * FROM performance_schema.session_connect_attrs;
+----------------+-----------------+------------+------------------+
| PROCESSLIST_ID | ATTR_NAME       | ATTR_VALUE | ORDINAL_POSITION |
+----------------+-----------------+------------+------------------+
|             20 | _pid            | 713027     |                0 |
|             20 | _platform       | x86_64     |                1 |
|             20 | _os             | Linux      |                2 |
|             20 | _client_name    | libmysql   |                3 |
|             20 | _client_version | 8.0.33     |                4 |
|             20 | program_name    | mysqlsh    |                5 |
+----------------+-----------------+------------+------------------+
6 rows in set (0.0039 sec)

Note the difference in ORDINAL_POSITION and information_schema vs performance_schema.

Update: Now moved to performance_schema.

[dveeden]

Comparing TiDB (on port 4000) with MySQL (on port 3306):

[dvaneeden@dve-carbon tidb]$ mysqlsh 'mysql://root@127.0.0.1:4000/test?connection-attributes=[tidb=rocks,]' --table -e "TABLE performance_schema.session_connect_attrs"
+----------------+-----------------+------------+------------------+
| PROCESSLIST_ID | ATTR_NAME       | ATTR_VALUE | ORDINAL_POSITION |
+----------------+-----------------+------------+------------------+
|  2199023255961 | _client_name    | libmysql   |                0 |
|  2199023255961 | _client_version | 8.0.33     |                1 |
|  2199023255961 | _os             | Linux      |                2 |
|  2199023255961 | _pid            | 925769     |                3 |
|  2199023255961 | _platform       | x86_64     |                4 |
|  2199023255961 | program_name    | mysqlsh    |                5 |
|  2199023255961 | tidb            | rocks      |                6 |
+----------------+-----------------+------------+------------------+
[dvaneeden@dve-carbon tidb]$ mysqlsh 'mysql://root:root@127.0.0.1/test?connection-attributes=[tidb=rocks,]' --table -e "TABLE performance_schema.session_connect_attrs"
+----------------+-----------------+------------+------------------+
| PROCESSLIST_ID | ATTR_NAME       | ATTR_VALUE | ORDINAL_POSITION |
+----------------+-----------------+------------+------------------+
|             32 | _platform       | x86_64     |                0 |
|             32 | _os             | Linux      |                1 |
|             32 | _client_name    | libmysql   |                2 |
|             32 | _pid            | 925806     |                3 |
|             32 | tidb            | rocks      |                4 |
|             32 | _client_version | 8.0.33     |                5 |
|             32 | program_name    | mysqlsh    |                6 |
+----------------+-----------------+------------+------------------+

[Benjamin2037]

LGTM

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Benjamin2037, tiancaiamao

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2023-06-09 01:37:37.464197455 +0000 UTC m=+48671.712119279: ☑️ agreed by tiancaiamao.
• 2023-06-12 18:38:26.02845137 +0000 UTC m=+24502.443055450: ☑️ agreed by Benjamin2037.

[dveeden]

/retest