--- sidebar_position: 110 --- # groupArray Syntax: `groupArray(x)` or `groupArray(max_size)(x)` Creates an array of argument values. Values can be added to the array in any (indeterminate) order. The second version (with the `max_size` parameter) limits the size of the resulting array to `max_size` elements. For example, `groupArray(1)(x)` is equivalent to `[any (x)]`. 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`. **Example** ``` text SELECT * FROM default.ck; ┌─id─┬─name─────┐ │ 1 │ zhangsan │ │ 1 │ ᴺᵁᴸᴸ │ │ 1 │ lisi │ │ 2 │ wangwu │ └────┴──────────┘ ``` Query: ``` sql select id, groupArray(10)(name) from default.ck group by id; ``` Result: ``` text ┌─id─┬─groupArray(10)(name)─┐ │ 1 │ ['zhangsan','lisi'] │ │ 2 │ ['wangwu'] │ └────┴──────────────────────┘ ``` The groupArray function will remove ᴺᵁᴸᴸ value based on the above results.