map_from_arrays

Creates a MAP value from the given pair of key item array and value item array.

This function is supported from v3.1 onwards.

Syntax

Haskell

MAP map_from_arrays(ARRAY keys, ARRAY values)

Parameters

keys: uses to construct the keys of the result MAP. Make sure the elements of keys are unique.
values: used to construct the values of the result MAP.

Return value

Returns a MAP that is constructed from the input keys and values.

Keys and values must have the same length, otherwise it will return an error.
If key or value is NULL, this function returns NULL.
The returned MAP value has distinct keys.

Examples

Plaintext

select map_from_arrays([1, 2], ['Star', 'Rocks']);
+--------------------------------------------+
| map_from_arrays([1, 2], ['Star', 'Rocks']) |
+--------------------------------------------+
| {1:"Star",2:"Rocks"}                       |
+--------------------------------------------+

Plaintext

select map_from_arrays([1, 2], NULL);
+-------------------------------+
| map_from_arrays([1, 2], NULL) |
+-------------------------------+
| NULL                          |
+-------------------------------+

select map_from_arrays([1,3,null,2,null],['ab','cdd',null,null,'abc']);
+--------------------------------------------------------------------------+
| map_from_arrays([1, 3, NULL, 2, NULL], ['ab', 'cdd', NULL, NULL, 'abc']) |
+--------------------------------------------------------------------------+
| {1:"ab",3:"cdd",2:null,null:"abc"}                                       |
+--------------------------------------------------------------------------+