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* Cleanup DataTypeCustomSimpleAggregateFunction::checkSupportedFunctions() Signed-off-by: Azat Khuzhin <a.khuzhin@semrush.com> * Remove unused GroupArrayGeneralListImpl Signed-off-by: Azat Khuzhin <a.khuzhin@semrush.com> * Introduce groupArrayLast() (useful to store last X values) Also do some refactoring to make code cleaner: - rename insert() to insertWithSampler() (since it is used only for groupArraySample()) - split merge methods into Last/RNG/... Signed-off-by: Azat Khuzhin <a.khuzhin@semrush.com> Signed-off-by: Azat Khuzhin <a.khuzhin@semrush.com>
42 lines
776 B
Markdown
42 lines
776 B
Markdown
---
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slug: /en/sql-reference/aggregate-functions/reference/grouparraylast
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sidebar_position: 110
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---
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# groupArrayLast
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Syntax: `groupArrayLast(max_size)(x)`
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Creates an array of last argument values.
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For example, `groupArrayLast(1)(x)` is equivalent to `[anyLast (x)]`.
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In some cases, you can still rely on the order of execution. This applies to cases when `SELECT` comes from a subquery that uses `ORDER BY`.
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**Example**
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Query:
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```sql
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select groupArrayLast(2)(number+1) numbers from numbers(10)
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```
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Result:
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```text
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┌─numbers─┐
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│ [9,10] │
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└─────────┘
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```
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In compare to `groupArray`:
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```sql
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select groupArray(2)(number+1) numbers from numbers(10)
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```
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```text
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┌─numbers─┐
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│ [1,2] │
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└─────────┘
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```
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