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* prefer relative links from root * wip * split aggregate function reference * split system tables
26 lines
749 B
Markdown
26 lines
749 B
Markdown
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toc_priority: 191
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---
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# uniqExact {#agg_function-uniqexact}
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Calculates the exact number of different argument values.
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``` sql
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uniqExact(x[, ...])
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```
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Use the `uniqExact` function if you absolutely need an exact result. Otherwise use the [uniq](uniq.md#agg_function-uniq) function.
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The `uniqExact` function uses more memory than `uniq`, because the size of the state has unbounded growth as the number of different values increases.
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**Parameters**
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The function takes a variable number of parameters. Parameters can be `Tuple`, `Array`, `Date`, `DateTime`, `String`, or numeric types.
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**See Also**
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- [uniq](uniq.md#agg_function-uniq)
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- [uniqCombined](uniq.md#agg_function-uniqcombined)
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- [uniqHLL12](uniq.md#agg_function-uniqhll12)
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