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- There is a latex formula in the documentation of the [covarPop](https://clickhouse.com/docs/en/sql-reference/aggregate-functions/reference/covarpop) method, which is quite similar to varPop method. - In Russian docs there are formulas both for [varPop](https://clickhouse.com/docs/ru/sql-reference/aggregate-functions/reference/varpop), and [covarPop](https://clickhouse.com/docs/ru/sql-reference/aggregate-functions/reference/covarpop). Therefore, for consistency, it is suggested to add formula here too.
57 lines
903 B
Markdown
57 lines
903 B
Markdown
---
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title: "varPop"
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slug: "/en/sql-reference/aggregate-functions/reference/varPop"
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sidebar_position: 210
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---
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## varPop
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Calculates the population variance:
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$$
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\frac{\Sigma{(x - \bar{x})^2}}{n}
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$$
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**Syntax**
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```sql
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varPop(x)
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```
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Alias: `VAR_POP`.
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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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varPop(x) AS var_pop
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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─┐
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│ 14.4 │
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└─────────┘
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```
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