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Update optimizer-fix-controls.md (#19515) #19591

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Dec 5, 2024
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Update optimizer-fix-controls.md (#19515) #19591

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Update optimizer-fix-controls.md
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lilin90 Dec 5, 2024
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Expand Up @@ -77,3 +77,10 @@
- Possible values: `ON`, `OFF`
- As stated in the **Note** of [Explain Statements Using Index Merge](/explain-index-merge.md#examples), if the optimizer can choose the single index scan method (other than full table scan) for a query plan, the optimizer will not automatically use index merge.
- You can remove this limitation by enabling this fix control. Removing this limitation enables the optimizer to choose index merge automatically in more queries, but might cause the optimizer to ignore the optimal execution plans. Therefore, it is recommended to conduct sufficient tests on actual use cases before removing this limitation to make sure that it will not cause performance regressions.

### [`54337`](https://github.com/pingcap/tidb/issues/54337) <span class="version-mark">New in v8.2.0</span>

- Default value: `OFF`
- Possible values: `ON`, `OFF`
- Currently, the TiDB optimizer has limitations in deriving index ranges for complex conjunctive conditions where each conjunct comprises a list of ranges. This can be addressed by applying general range intersection.
- You can remove this limitation by enabling this fix control, allowing the optimizer to handle complex range intersections. However, for conditions with a large number of conjuncts (more than 10), there is a slight risk of increased optimization time.

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[vale] reported by reviewdog 🐶
[PingCAP.Ambiguous] Consider using a clearer word than 'a large number of' because it may cause confusion.

Raw Output:
{"message": "[PingCAP.Ambiguous] Consider using a clearer word than 'a large number of' because it may cause confusion.", "location": {"path": "optimizer-fix-controls.md", "range": {"start": {"line": 86, "column": 155}}}, "severity": "INFO"}
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