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include compatibility notice for tidb_remove_orderby_in_subquery #20684

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include compatibility notice for tidb_remove_orderby_in_subquery #20684

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86e56f0
include notice in release note
songrijie Apr 1, 2025
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accept suggestions from bot
songrijie Apr 10, 2025
40abbde
Update release-7.2.0.md
hfxsd Apr 10, 2025
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Update release-7.2.0.md
hfxsd Apr 11, 2025
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Update release-7.2.0.md
hfxsd Apr 11, 2025
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1 change: 1 addition & 0 deletions releases/release-7.2.0.md
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Expand Up @@ -173,6 +173,7 @@
### Behavior changes

- When processing update event, TiCDC splits an event into delete and insert events if the primary key or non-null unique index value is modified in the event. For more information, see [documentation](/ticdc/ticdc-split-update-behavior.md#transactions-containing-a-single-update-change).
- Changes the default value of [`tidb_remove_orderby_in_subquery`](/system-variables.md#tidb_remove_orderby_in_subquery-new-in-v610) from `OFF` to `ON`, meaning that the optimizer removes the `ORDER BY` clause in a subquery. This can avoid unnecessary sorting operations, which improves query performance in many cases. This change might result in a different order of query results. The ISO/IEC SQL standard does not require query results to follow the `ORDER BY` sorting of subqueries. To strictly guarantee the final result order, sorting must be explicitly included in the outer query. If your applications rely on subquery sorting, you can set this variable to `OFF`. Clusters upgraded from earlier versions retain the previous behavior by default.

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[PingCAP.Ambiguous] Consider using a clearer word than 'many' because it may cause confusion.

Raw Output:
{"message": "[PingCAP.Ambiguous] Consider using a clearer word than 'many' because it may cause confusion.", "location": {"path": "releases/release-7.2.0.md", "range": {"start": {"line": 176, "column": 309}}}, "severity": "INFO"}

### System variables

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