ClickHouse/docs/en/sql-reference/aggregate-functions/reference/grouparraysample.md

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toc_priority: 114
---
# groupArraySample {#grouparraysample}
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.
**Syntax**
``` sql
groupArraySample(max_size[, seed])(x)
```
**Arguments**
- `max_size` — Maximum size of the resulting array. [UInt64](../../data-types/int-uint.md).
- `seed` — Seed for the random number generator. Optional. [UInt64](../../data-types/int-uint.md). Default value: `123456`.
- `x` — Argument (column name or expression).
**Returned values**
- Array of randomly selected `x` arguments.
Type: [Array](../../data-types/array.md).
**Examples**
Consider table `colors`:
``` text
┌─id─┬─color──┐
│ 1 │ red │
│ 2 │ blue │
│ 3 │ green │
│ 4 │ white │
│ 5 │ orange │
└────┴────────┘
```
Query with column name as argument:
``` sql
SELECT groupArraySample(3)(color) as newcolors FROM colors;
```
Result:
```text
┌─newcolors──────────────────┐
│ ['white','blue','green'] │
└────────────────────────────┘
```
Query with column name and different seed:
``` sql
SELECT groupArraySample(3, 987654321)(color) as newcolors FROM colors;
```
Result:
```text
┌─newcolors──────────────────┐
│ ['red','orange','green'] │
└────────────────────────────┘
```
Query with expression as argument:
``` sql
SELECT groupArraySample(3)(concat('light-', color)) as newcolors FROM colors;
```
Result:
```text
┌─newcolors───────────────────────────────────┐
│ ['light-blue','light-orange','light-green'] │
└─────────────────────────────────────────────┘
```