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docs/en/sql-reference/aggregate-functions/reference/uniq.md
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@ -38,3 +38,4 @@ We recommend using this function in almost all scenarios.
- [uniqCombined64](../../../sql-reference/aggregate-functions/reference/uniqcombined64.md#agg_function-uniqcombined64)
- [uniqHLL12](../../../sql-reference/aggregate-functions/reference/uniqhll12.md#agg_function-uniqhll12)
- [uniqExact](../../../sql-reference/aggregate-functions/reference/uniqexact.md#agg_function-uniqexact)
- [uniqThetaSketch](../../../sql-reference/aggregate-functions/reference/uniqthetasketch.md#agg_function-uniqthetasketch)

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docs/en/sql-reference/aggregate-functions/reference/uniqcombined.md
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@ -49,3 +49,4 @@ Compared to the [uniq](../../../sql-reference/aggregate-functions/reference/uniq
- [uniqCombined64](../../../sql-reference/aggregate-functions/reference/uniqcombined64.md#agg_function-uniqcombined64)
- [uniqHLL12](../../../sql-reference/aggregate-functions/reference/uniqhll12.md#agg_function-uniqhll12)
- [uniqExact](../../../sql-reference/aggregate-functions/reference/uniqexact.md#agg_function-uniqexact)
- [uniqThetaSketch](../../../sql-reference/aggregate-functions/reference/uniqthetasketch.md#agg_function-uniqthetasketch)

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docs/en/sql-reference/aggregate-functions/reference/uniqexact.md
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@ -23,3 +23,4 @@ The function takes a variable number of parameters. Parameters can be `Tuple`, `
- [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)
- [uniqThetaSketch](../../../sql-reference/aggregate-functions/reference/uniqthetasketch.md#agg_function-uniqthetasketch)

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docs/en/sql-reference/aggregate-functions/reference/uniqhll12.md
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@ -37,3 +37,4 @@ We don’t recommend using this function. In most cases, use the [uniq](../../..
- [uniq](../../../sql-reference/aggregate-functions/reference/uniq.md#agg_function-uniq)
- [uniqCombined](../../../sql-reference/aggregate-functions/reference/uniqcombined.md#agg_function-uniqcombined)
- [uniqExact](../../../sql-reference/aggregate-functions/reference/uniqexact.md#agg_function-uniqexact)
- [uniqThetaSketch](../../../sql-reference/aggregate-functions/reference/uniqthetasketch.md#agg_function-uniqthetasketch)

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---
toc_priority: 195
---
# uniqThetaSketch {#agg_function-uniqthetasketch}
Calculates the approximate number of different argument values, using the [Theta Sketch Framework](https://datasketches.apache.org/docs/Theta/ThetaSketchFramework.html).
``` sql
uniqThetaSketch(x[, ...])
```
**Arguments**
The function takes a variable number of parameters. Parameters can be `Tuple`, `Array`, `Date`, `DateTime`, `String`, or numeric types.
**Returned value**
- A [UInt64](../../../sql-reference/data-types/int-uint.md)-type number.
**Implementation details**
Function:
- Calculates a hash for all parameters in the aggregate, then uses it in calculations.
- Uses the [KMV](https://datasketches.apache.org/docs/Theta/InverseEstimate.html) algorithm to approximate the number of different argument values.
4096(2^12) 64-bit sketch are used. The size of the state is about 41 KB.
- The relative error is 3.125% (95% confidence), see the [relative error table](https://datasketches.apache.org/docs/Theta/ThetaErrorTable.html) for detail.
**See Also**
- [uniq](../../../sql-reference/aggregate-functions/reference/uniq.md#agg_function-uniq)
- [uniqCombined](../../../sql-reference/aggregate-functions/reference/uniqcombined.md#agg_function-uniqcombined)
- [uniqCombined64](../../../sql-reference/aggregate-functions/reference/uniqcombined64.md#agg_function-uniqcombined64)
- [uniqHLL12](../../../sql-reference/aggregate-functions/reference/uniqhll12.md#agg_function-uniqhll12)
- [uniqExact](../../../sql-reference/aggregate-functions/reference/uniqexact.md#agg_function-uniqexact)