groupUniqArray

Syntax: groupUniqArray(x) or groupUniqArray(max_size)(x)

Creates an array from different argument values. Memory consumption is the same as for the uniqExact function.

The second version (with the max_size parameter) limits the size of the resulting array to max_size elements. For example, groupUniqArray(1)(x) is equivalent to [any(x)].

groupUniqArray

Introduced in: v1.1

Creates an array from different argument values. The memory consumption of this function is the same as for the uniqExact function.

Syntax

groupUniqArray(x)
groupUniqArray(max_size)(x)

Parameters

max_size — Limits the size of the resulting array to max_size elements. groupUniqArray(1)(x) is equivalent to [any(x)]. UInt64

Arguments

x — Expression. Any

Returned value

Returns an array of unique values. Array

Examples

Usage example

CREATE TABLE t (x UInt8) ENGINE = Memory;
INSERT INTO t VALUES (1), (2), (1), (3), (2), (4);

SELECT groupUniqArray(x) FROM t;

┌─groupUniqArray(x)─┐
│ [1,2,3,4]         │
└───────────────────┘

With max_size parameter

SELECT groupUniqArray(2)(x) FROM t;

┌─groupUniqArray(2)(x)─┐
│ [1,2]                │
└──────────────────────┘

groupUniqArray​

groupUniqArray