array_flatten

array_flatten flattens one layer of nested arrays.

Syntax

Haskell

array_flatten(param)

Parameters

param: a nested array that needs to be flattened. Only nested arrays are supported, and it can be a multi-level nested array, the elements of the array can be any data type supported by StarRocks.

Return value

The data type of the return value is an array type after flattening one layer.

Examples

Example 1: Flatten a 2-level nested array.

plaintext

mysql> SELECT array_flatten([[1, 2], [1, 4]]) as res;
+-----------+
| res       |
+-----------+
| [1,2,1,4] |
+-----------+

Example 2: Flatten a 3-level nested array.

plaintext

mysql> SELECT array_flatten([[[1],[2]], [[3],[4]]]) as res;
+-------------------+
| res               |
+-------------------+
| [[1],[2],[3],[4]] |
+-------------------+