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83 lines
2.1 KiB
Markdown
83 lines
2.1 KiB
Markdown
---
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slug: /en/sql-reference/aggregate-functions/reference/grouparraysample
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sidebar_position: 114
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---
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# groupArraySample
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Creates an array of sample argument values. The size of the resulting array is limited to `max_size` elements. Argument values are selected and added to the array randomly.
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**Syntax**
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``` sql
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groupArraySample(max_size[, seed])(x)
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```
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**Arguments**
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- `max_size` — Maximum size of the resulting array. [UInt64](../../data-types/int-uint.md).
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- `seed` — Seed for the random number generator. Optional. [UInt64](../../data-types/int-uint.md). Default value: `123456`.
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- `x` — Argument (column name or expression).
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**Returned values**
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- Array of randomly selected `x` arguments.
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Type: [Array](../../data-types/array.md).
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**Examples**
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Consider table `colors`:
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``` text
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┌─id─┬─color──┐
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│ 1 │ red │
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│ 2 │ blue │
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│ 3 │ green │
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│ 4 │ white │
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│ 5 │ orange │
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└────┴────────┘
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```
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Query with column name as argument:
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``` sql
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SELECT groupArraySample(3)(color) as newcolors FROM colors;
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```
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Result:
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```text
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┌─newcolors──────────────────┐
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│ ['white','blue','green'] │
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└────────────────────────────┘
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```
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Query with column name and different seed:
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``` sql
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SELECT groupArraySample(3, 987654321)(color) as newcolors FROM colors;
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```
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Result:
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```text
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┌─newcolors──────────────────┐
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│ ['red','orange','green'] │
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└────────────────────────────┘
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```
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Query with expression as argument:
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``` sql
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SELECT groupArraySample(3)(concat('light-', color)) as newcolors FROM colors;
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```
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Result:
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```text
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┌─newcolors───────────────────────────────────┐
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│ ['light-blue','light-orange','light-green'] │
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└─────────────────────────────────────────────┘
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```
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