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include compatibility notice for tidb_remove_orderby_in_subquery #20684

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Merged
ti-chi-bot merged 8 commits into from
May 20, 2025
Merged

include compatibility notice for tidb_remove_orderby_in_subquery #20684

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86e56f0
include notice in release note
songrijie Apr 1, 2025
17746e5
accept suggestions from bot
songrijie Apr 10, 2025
40abbde
Update release-7.2.0.md
hfxsd Apr 10, 2025
244cd5a
Update release-7.2.0.md
hfxsd Apr 11, 2025
6d4b7c9
Update release-7.2.0.md
hfxsd Apr 11, 2025
782d292
Update releases/release-7.2.0.md
hfxsd May 20, 2025
fe1756a
Merge remote-tracking branch 'upstream/master' into compatibility_not…
hfxsd May 20, 2025
fb1e452
fix links
hfxsd May 20, 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. You can set this variable to `OFF` for applications that rely on subquery sorting. Clusters upgraded from earlier versions retain the previous behavior by default.

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[vale] reported by reviewdog 🐶
[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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