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perf-tuning: update anchors in wrong-index-solution (#3934) #3935

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Jul 9, 2020
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perf-tuning: update anchors in wrong-index-solution (#3934) #3935

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4 changes: 2 additions & 2 deletions wrong-index-solution.md
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Expand Up @@ -16,9 +16,9 @@ category: performance

这时意味着刚刚结束 `ANALYZE` 命令或者结束后不久。这时可能和 TiDB 对行数的估算逻辑有关。

对于等值查询，在[统计信息简介](/statistics.md)中提到了一种可能的情况。这时可以先检查是不是这种特殊情况，然后进行对应的处理。
对于等值查询，错误索引可能是由 [Count-Min Sketch](/statistics.md#count-min-sketch) 引起的。这时可以先检查是不是这种特殊情况，然后进行对应的处理。

如果经过检查发现不是上面的可能情况，可以使用 [Optimizer Hints](/optimizer-hints.md) 中提到的 `USE_INDEX` 或者 `use index` 来强制选择索引。同时也可以使用[执行计划管理](/sql-plan-management.md)中提到的方式来非侵入地更改查询的行为。
如果经过检查发现不是上面的可能情况，可以使用 [Optimizer Hints](/optimizer-hints.md#use_indext1_name-idx1_name--idx2_name-) 中提到的 `USE_INDEX` 或者 `use index` 来强制选择索引。同时也可以使用[执行计划管理](/sql-plan-management.md)中提到的方式来非侵入地更改查询的行为。

## 其他情况

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