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53 lines
1.1 KiB
Markdown
53 lines
1.1 KiB
Markdown
---
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title: "varPopStable"
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slug: "/en/sql-reference/aggregate-functions/reference/varpopstable"
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sidebar_position: 211
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---
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## varPopStable
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Returns the population variance. Unlike [`varPop`](../reference/varpop.md), this function uses a [numerically stable](https://en.wikipedia.org/wiki/Numerical_stability) algorithm. It works slower but provides a lower computational error.
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**Syntax**
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```sql
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varPopStable(x)
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```
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Alias: `VAR_POP_STABLE`.
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**Parameters**
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- `x`: Population of values to find the population variance of. [(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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- Returns the population 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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x UInt8,
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)
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ENGINE = Memory;
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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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varPopStable(x) AS var_pop_stable
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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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┌─var_pop_stable─┐
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│ 14.4 │
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└────────────────┘
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```
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