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* translate [select] section into Chinese to improve readability * trigger ci Co-authored-by: mikepop7 <> Co-authored-by: Ivan Blinkov <github@blinkov.ru>
63 lines
1.4 KiB
Markdown
63 lines
1.4 KiB
Markdown
---
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toc_title: LIMIT
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---
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# LIMIT {#limit-clause}
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`LIMIT m` 允许选择结果中起始的 `m` 行。
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`LIMIT n, m` 允许选择个 `m` 从跳过第一个结果后的行 `n` 行。 与 `LIMIT m OFFSET n` 语法是等效的。
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`n` 和 `m` 必须是非负整数。
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如果没有 [ORDER BY](../../../sql-reference/statements/select/order-by.md) 子句显式排序结果，结果的行选择可能是任意的和非确定性的。
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## LIMIT … WITH TIES 修饰符 {#limit-with-ties}
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如果为 `LIMIT n[,m]` 设置了 `WITH TIES` ，并且声明了 `ORDER BY expr_list`, you will get in result first `n` or `n,m` rows and all rows with same `ORDER BY` fields values equal to row at position `n` for `LIMIT n` and `m` for `LIMIT n,m`.
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此修饰符可以与： [ORDER BY … WITH FILL modifier](../../../sql-reference/statements/select/order-by.md#orderby-with-fill) 组合使用.
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例如以下查询：
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``` sql
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SELECT * FROM (
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SELECT number%50 AS n FROM numbers(100)
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) ORDER BY n LIMIT 0,5
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```
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返回
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``` text
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┌─n─┐
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│ 0 │
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│ 0 │
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│ 1 │
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│ 1 │
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│ 2 │
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└───┘
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```
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单子执行了 `WITH TIES` 修饰符后
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``` sql
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SELECT * FROM (
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SELECT number%50 AS n FROM numbers(100)
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) ORDER BY n LIMIT 0,5 WITH TIES
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```
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则返回了以下的数据行
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``` text
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┌─n─┐
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│ 0 │
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│ 0 │
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│ 1 │
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│ 1 │
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│ 2 │
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│ 2 │
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└───┘
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```
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cause row number 6 have same value “2” for field `n` as row number 5
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