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49 lines
1.2 KiB
Markdown
49 lines
1.2 KiB
Markdown
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---
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slug: /en/sql-reference/aggregate-functions/reference/stddevsampstable
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sidebar_position: 31
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---
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# stddevSampStable
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The result is equal to the square root of [varSamp](../../../sql-reference/aggregate-functions/reference/varsamp.md). Unlike [`stddevSamp`](../reference/stddevsamp.md) This function uses a numerically stable algorithm. It works slower but provides a lower computational error.
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**Syntax**
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```sql
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stddevSampStable(x)
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```
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**Parameters**
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- `x`: Values for which to find the square root of sample variance. [(U)Int*](../../data-types/int-uint.md), [Float*](../../data-types/float.md), [Decimal*](../../data-types/decimal.md).
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**Returned value**
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Square root of sample variance of `x`. [Float64](../../data-types/float.md).
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**Example**
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Query:
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```sql
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DROP TABLE IF EXISTS test_data;
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CREATE TABLE test_data
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(
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population UInt8,
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)
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ENGINE = Log;
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INSERT INTO test_data VALUES (3),(3),(3),(4),(4),(5),(5),(7),(11),(15);
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SELECT
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stddevSampStable(population)
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FROM test_data;
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```
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Result:
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```response
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┌─stddevSampStable(population)─┐
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│ 4 │
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└──────────────────────────────┘
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```
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