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docs/zh/sql-reference/data-types/simpleaggregatefunction.md
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---
machine_translated: true
machine_translated_rev: 71d72c1f237f4a553fe91ba6c6c633e81a49e35b
---
# SimpleAggregateFunction {#data-type-simpleaggregatefunction}
`SimpleAggregateFunction(name, types_of_arguments…)` 数据类型存储聚合函数的当前值，而不将其完整状态存储为 [`AggregateFunction`](../../sql-reference/data-types/aggregatefunction.md) 有 此优化可应用于具有以下属性的函数：应用函数的结果 `f` 到行集 `S1 UNION ALL S2` 可以通过应用来获得 `f` 行的部分单独设置，然后再次应用 `f` 到结果: `f(S1 UNION ALL S2) = f(f(S1) UNION ALL f(S2))`. 此属性保证部分聚合结果足以计算组合结果，因此我们不必存储和处理任何额外的数据。
`SimpleAggregateFunction(name, types_of_arguments…)` 数据类型存储聚合函数的当前值, 并不像 [`AggregateFunction`](../../sql-reference/data-types/aggregatefunction.md) 那样存储其全部状态。这种优化可以应用于具有以下属性函数: 将函数 `f` 应用于行集合 `S1 UNION ALL S2` 的结果，可以通过将 `f` 分别应用于行集合的部分, 然后再将 `f` 应用于结果来获得: `f(S1 UNION ALL S2) = f(f(S1) UNION ALL f(S2))`。 这个属性保证了部分聚合结果足以计算出合并的结果，所以我们不必存储和处理任何额外的数据。
支持以下聚合函数:
- [`any`](../../sql-reference/aggregate-functions/reference.md#agg_function-any)
- [`anyLast`](../../sql-reference/aggregate-functions/reference.md#anylastx)
- [`min`](../../sql-reference/aggregate-functions/reference.md#agg_function-min)
- [`max`](../../sql-reference/aggregate-functions/reference.md#agg_function-max)
- [`sum`](../../sql-reference/aggregate-functions/reference.md#agg_function-sum)
- [`groupBitAnd`](../../sql-reference/aggregate-functions/reference.md#groupbitand)
- [`groupBitOr`](../../sql-reference/aggregate-functions/reference.md#groupbitor)
- [`groupBitXor`](../../sql-reference/aggregate-functions/reference.md#groupbitxor)
- [`groupArrayArray`](../../sql-reference/aggregate-functions/reference.md#agg_function-grouparray)
- [`groupUniqArrayArray`](../../sql-reference/aggregate-functions/reference.md#groupuniqarrayx-groupuniqarraymax-sizex)
- [`any`](../../sql-reference/aggregate-functions/reference/any.md#agg_function-any)
- [`anyLast`](../../sql-reference/aggregate-functions/reference/anylast.md#anylastx)
- [`min`](../../sql-reference/aggregate-functions/reference/min.md#agg_function-min)
- [`max`](../../sql-reference/aggregate-functions/reference/max.md#agg_function-max)
- [`sum`](../../sql-reference/aggregate-functions/reference/sum.md#agg_function-sum)
- [`sumWithOverflow`](../../sql-reference/aggregate-functions/reference/sumwithoverflow.md#sumwithoverflowx)
- [`groupBitAnd`](../../sql-reference/aggregate-functions/reference/groupbitand.md#groupbitand)
- [`groupBitOr`](../../sql-reference/aggregate-functions/reference/groupbitor.md#groupbitor)
- [`groupBitXor`](../../sql-reference/aggregate-functions/reference/groupbitxor.md#groupbitxor)
- [`groupArrayArray`](../../sql-reference/aggregate-functions/reference/grouparray.md#agg_function-grouparray)
- [`groupUniqArrayArray`](../../sql-reference/aggregate-functions/reference/groupuniqarray.md)
- [`sumMap`](../../sql-reference/aggregate-functions/reference/summap.md#agg_functions-summap)
- [`minMap`](../../sql-reference/aggregate-functions/reference/minmap.md#agg_functions-minmap)
- [`maxMap`](../../sql-reference/aggregate-functions/reference/maxmap.md#agg_functions-maxmap)
- [`argMin`](../../sql-reference/aggregate-functions/reference/argmin.md)
- [`argMax`](../../sql-reference/aggregate-functions/reference/argmax.md)
的值 `SimpleAggregateFunction(func, Type)` 看起来和存储方式相同 `Type`，所以你不需要应用函数 `-Merge`/`-State` 后缀。 `SimpleAggregateFunction` 具有比更好的性能 `AggregateFunction` 具有相同的聚合功能。
!!! note "注"
`SimpleAggregateFunction(func, Type)` 的值外观和存储方式于 `Type` 相同, 所以你不需要应用带有 `-Merge`/`-State` 后缀的函数。
`SimpleAggregateFunction` 的性能优于具有相同聚合函数的 `AggregateFunction` 。
**参数**
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**示例**
``` sql
CREATE TABLE t
(
column1 SimpleAggregateFunction(sum, UInt64),
column2 SimpleAggregateFunction(any, String)
) ENGINE = ...
CREATE TABLE simple (id UInt64, val SimpleAggregateFunction(sum, Double)) ENGINE=AggregatingMergeTree ORDER BY id;
```
[原始文章](https://clickhouse.tech/docs/en/data_types/simpleaggregatefunction/) <!--hide-->