ClickHouse/docs/en/sql-reference/aggregate-functions/reference/uniqexact.md

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slug: /en/sql-reference/aggregate-functions/reference/uniqexact
sidebar_position: 191
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# uniqExact

Calculates the exact number of different argument values.

``` sql
uniqExact(x[, ...])
```

Use the `uniqExact` function if you absolutely need an exact result. Otherwise use the [uniq](../../../sql-reference/aggregate-functions/reference/uniq.md#agg_function-uniq) function.

The `uniqExact` function uses more memory than `uniq`, because the size of the state has unbounded growth as the number of different values increases.

**Arguments**

The function takes a variable number of parameters. Parameters can be `Tuple`, `Array`, `Date`, `DateTime`, `String`, or numeric types.

**See Also**

-   [uniq](../../../sql-reference/aggregate-functions/reference/uniq.md#agg_function-uniq)
-   [uniqCombined](../../../sql-reference/aggregate-functions/reference/uniq.md#agg_function-uniqcombined)
-   [uniqHLL12](../../../sql-reference/aggregate-functions/reference/uniq.md#agg_function-uniqhll12)
-   [uniqTheta](../../../sql-reference/aggregate-functions/reference/uniqthetasketch.md#agg_function-uniqthetasketch)
[docs] split aggregate function and system table references (#11742) * prefer relative links from root * wip * split aggregate function reference * split system tables 2020-06-18 08:24:31 +00:00			`---`
add slugs 2022-08-28 14:53:34 +00:00			`slug: /en/sql-reference/aggregate-functions/reference/uniqexact`
Removed /ja folder, cleaned up /ru markdown 2022-04-09 13:29:05 +00:00			`sidebar_position: 191`
[docs] split aggregate function and system table references (#11742) * prefer relative links from root * wip * split aggregate function reference * split system tables 2020-06-18 08:24:31 +00:00			`---`

Remove H1 anchor tags from docs 2022-06-02 10:55:18 +00:00			`# uniqExact`
[docs] split aggregate function and system table references (#11742) * prefer relative links from root * wip * split aggregate function reference * split system tables 2020-06-18 08:24:31 +00:00
			`Calculates the exact number of different argument values.`

			``` sql
			`uniqExact(x[, ...])`
			```

[docs] split various kinds of CREATE queries into separate articles (#12328) * normalize * split & adjust links * re-normalize * adjust ru links * adjust ja/tr links * partially apply e0d19d2aeaeafa3620305bce3a991fefc0e28695 * reset contribs 2020-07-09 15:10:35 +00:00			Use the `uniqExact` function if you absolutely need an exact result. Otherwise use the [uniq](../../../sql-reference/aggregate-functions/reference/uniq.md#agg_function-uniq) function.
[docs] split aggregate function and system table references (#11742) * prefer relative links from root * wip * split aggregate function reference * split system tables 2020-06-18 08:24:31 +00:00
			The `uniqExact` function uses more memory than `uniq`, because the size of the state has unbounded growth as the number of different values increases.

Replacement `Parameters` to `Arguments` for aggregate functions 2021-02-15 21:33:53 +00:00			`Arguments`
[docs] split aggregate function and system table references (#11742) * prefer relative links from root * wip * split aggregate function reference * split system tables 2020-06-18 08:24:31 +00:00
			The function takes a variable number of parameters. Parameters can be `Tuple`, `Array`, `Date`, `DateTime`, `String`, or numeric types.

			`See Also`

[docs] split various kinds of CREATE queries into separate articles (#12328) * normalize * split & adjust links * re-normalize * adjust ru links * adjust ja/tr links * partially apply e0d19d2aeaeafa3620305bce3a991fefc0e28695 * reset contribs 2020-07-09 15:10:35 +00:00			`- [uniq](../../../sql-reference/aggregate-functions/reference/uniq.md#agg_function-uniq)`
			`- [uniqCombined](../../../sql-reference/aggregate-functions/reference/uniq.md#agg_function-uniqcombined)`
			`- [uniqHLL12](../../../sql-reference/aggregate-functions/reference/uniq.md#agg_function-uniqhll12)`
Raname uniqThetaSketch to uniqTheta 2021-05-11 14:36:26 +00:00			`- [uniqTheta](../../../sql-reference/aggregate-functions/reference/uniqthetasketch.md#agg_function-uniqthetasketch)`