Map Functions

element_at(map(K, V), key) → V

Returns value for given key, or NULL if the key is not contained in the map.

map(K, V, K, V, ...) -> map(K, V)

Returns a map created using the given key/value pairs. Keys are not allowed to be null.

SELECT map(1, 2, 3, 4); -- {1 -> 2, 3 -> 4}

SELECT map(array(1, 2), array(3, 4)); -- {[1, 2] -> [3, 4]}

map_filter(map(K, V), func) -> map(K, V)

Filters entries in a map using the function.

SELECT map_filter(map(1, 0, 2, 2, 3, -1), (k, v) -> k > v); -- {1 -> 0, 3 -> -1}

map_from_arrays(array(K), array(V)) -> map(K, V)

Creates a map with a pair of the given key/value arrays. All elements in keys should not be null. If key size != value size will throw exception that key and value must have the same length.:

SELECT map_from_arrays(array(1.0, 3.0), array('2', '4')); -- {1.0 -> 2, 3.0 -> 4}

size(map(K, V)) → bigint

Returns the size of the input map. Returns null for null input if spark.legacy_size_of_null is set to false. Otherwise, returns -1 for null input.