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40 lines
1.2 KiB
Markdown
40 lines
1.2 KiB
Markdown
---
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toc_priority: 145
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---
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# sumKahan {#agg_function-sumKahan}
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Calculates the sum of the numbers with [Kahan compensated summation algorithm](https://en.wikipedia.org/wiki/Kahan_summation_algorithm)
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Slower than [sum](./sum.md) function.
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The compensation works only for [Float](../../../sql-reference/data-types/float.md) types.
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**Syntax**
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``` sql
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sumKahan(x)
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```
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**Arguments**
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- `x` — Input value, must be [Integer](../../../sql-reference/data-types/int-uint.md), [Float](../../../sql-reference/data-types/float.md), or [Decimal](../../../sql-reference/data-types/decimal.md).
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**Returned value**
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- the sum of numbers, with type [Integer](../../../sql-reference/data-types/int-uint.md), [Float](../../../sql-reference/data-types/float.md), or [Decimal](../../../sql-reference/data-types/decimal.md) depends on type of input arguments
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**Example**
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Query:
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``` sql
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SELECT sum(0.1), sumKahan(0.1) FROM numbers(10);
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```
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Result:
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``` text
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┌───────────sum(0.1)─┬─sumKahan(0.1)─┐
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│ 0.9999999999999999 │ 1 │
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└────────────────────┴───────────────┘
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``` |