tidb-functions: add info about special start_key/end_key values

[dveeden]

What is changed, added or deleted? (Required)

sql> SELECT TABLE_NAME, REGION_ID, START_KEY, END_KEY FROM information_schema.TIKV_REGION_STATUS WHERE TABLE_NAME='stock' AND IS_INDEX=0;
+------------+-----------+--------------------------------------------------------+--------------------------------------------------------+
| TABLE_NAME | REGION_ID | START_KEY                                              | END_KEY                                                |
+------------+-----------+--------------------------------------------------------+--------------------------------------------------------+
| stock      |        74 | 7480000000000000FF4700000000000000F8                   | 7480000000000000FF475F728000000000FF029DF00000000000FA |
| stock      |        72 | 7480000000000000FF475F728000000000FF0D7ECA0000000000FA | 7480000000000000FF4900000000000000F8                   |
| stock      |        78 | 7480000000000000FF475F728000000000FF063E890000000000FA | 7480000000000000FF475F728000000000FF09E0350000000000FA |
| stock      |        76 | 7480000000000000FF475F728000000000FF029DF00000000000FA | 7480000000000000FF475F728000000000FF063E890000000000FA |
| stock      |        80 | 7480000000000000FF475F728000000000FF09E0350000000000FA | 7480000000000000FF475F728000000000FF0D7ECA0000000000FA |
+------------+-----------+--------------------------------------------------------+--------------------------------------------------------+
5 rows in set (0.0144 sec)

sql> SELECT TIDB_DECODE_KEY('7480000000000000FF4700000000000000F8');
+---------------------------------------------------------+
| TIDB_DECODE_KEY('7480000000000000FF4700000000000000F8') |
+---------------------------------------------------------+
| 7480000000000000FF4700000000000000F8                    |
+---------------------------------------------------------+
1 row in set, 1 warning (0.0013 sec)
Warning (code 1105): invalid record/index key: 748000000000000047

sql> SELECT TIDB_DECODE_KEY('7480000000000000FF475F728000000000FF0D7ECA0000000000FA');
+---------------------------------------------------------------------------+
| TIDB_DECODE_KEY('7480000000000000FF475F728000000000FF0D7ECA0000000000FA') |
+---------------------------------------------------------------------------+
| {"_tidb_rowid":884426,"table_id":"71"}                                    |
+---------------------------------------------------------------------------+
1 row in set (0.0013 sec)

sql> SELECT TABLE_NAME, REGION_ID, TIDB_DECODE_KEY(START_KEY) sk, TIDB_DECODE_KEY(END_KEY) ek FROM information_schema.TIKV_REGION_STATUS WHERE TABLE_NAME='stock' AND IS_INDEX=0 ORDER BY IF(JSON_VALID(sk),sk->'$."_tidb_rowid"',0);
+------------+-----------+----------------------------------------+----------------------------------------+
| TABLE_NAME | REGION_ID | sk                                     | ek                                     |
+------------+-----------+----------------------------------------+----------------------------------------+
| stock      |        74 | 7480000000000000FF4700000000000000F8   | {"_tidb_rowid":171504,"table_id":"71"} |
| stock      |        76 | {"_tidb_rowid":171504,"table_id":"71"} | {"_tidb_rowid":409225,"table_id":"71"} |
| stock      |        78 | {"_tidb_rowid":409225,"table_id":"71"} | {"_tidb_rowid":647221,"table_id":"71"} |
| stock      |        80 | {"_tidb_rowid":647221,"table_id":"71"} | {"_tidb_rowid":884426,"table_id":"71"} |
| stock      |        72 | {"_tidb_rowid":884426,"table_id":"71"} | 7480000000000000FF4900000000000000F8   |
+------------+-----------+----------------------------------------+----------------------------------------+
5 rows in set, 2 warnings (0.0133 sec)
Warning (code 1105): invalid record/index key: 748000000000000047
Warning (code 1105): invalid record/index key: 748000000000000049

Which TiDB version(s) do your changes apply to? (Required)

• [x] master (the latest development version)
• [x] v5.4 (TiDB 5.4 versions)
• [x] v5.3 (TiDB 5.3 versions)
• [x] v5.2 (TiDB 5.2 versions)
• [ ] v5.1 (TiDB 5.1 versions)
• [ ] v5.0 (TiDB 5.0 versions)
• [ ] v4.0 (TiDB 4.0 versions)
• [ ] v3.1 (TiDB 3.1 versions)
• [ ] v3.0 (TiDB 3.0 versions)
• [ ] v2.1 (TiDB 2.1 versions)

[ti-chi-bot]

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[dveeden]

/cc @kolbe

[kolbe]

@dveeden this is great, but maybe you could also submit a patch to tidb to make tidb_decode_key do something more sensible with these values 🙂

[dveeden]

@kolbe yes, that's my plan.

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[dveeden]

/label needs-cherry-pick-release-5.2

[dveeden]

/cc @morgo

[dveeden]

/label needs-cherry-pick-release-5.4

[qiancai]

Removed the needs-cherry-pick-release-6.3 label because the v6.3 docs have been archived at https://docs-archive.pingcap.com/tidb/v6.3 and will no longer receive new updates.

[qiancai]

Removed the needs-cherry-pick-release-6.4 label because the v6.4 docs have been archived at https://docs-archive.pingcap.com/tidb/v6.4 and will no longer receive new updates.

[qiancai]

Removed the needs-cherry-pick-release-6.6 label because the v6.6 docs have been archived at https://docs-archive.pingcap.com/tidb/v6.6 and will no longer receive new updates.

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[ti-chi-bot[bot]]

[LGTM Timeline notifier]

Timeline:

• 2023-11-29 03:37:43.171066764 +0000 UTC m=+980291.836292958: :ballot_box_with_check: agreed by Oreoxmt.
• 2023-11-30 07:24:19.746465569 +0000 UTC m=+1080288.411691765: :ballot_box_with_check: agreed by ran-huang.

[Oreoxmt]

/approve

[ti-chi-bot[bot]]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Oreoxmt

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[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-7.1: #15604.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-7.5: #15605.

[RobertCheng-956]

/assign

[RobertCheng-956]

/translation done

[RobertCheng-956]

/remove-translation welcome