ClickHouse/docs/en/sql-reference/aggregate-functions/reference/uniqexact.md
2022-04-04 02:05:35 +03:00

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# uniqExact {#agg_function-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)