Map Functions¶
- element_at(map(K, V), key) V¶
Returns value for given
key, orNULLif the key is not contained in the map.
- map()¶
Returns an empty map.
SELECT map(); -- {}
- map(array(K), array(V)) -> map(K, V)
Returns a map created using the given key/value arrays. Duplicate map key will cause exception.
SELECT map(ARRAY[1,3], ARRAY[2,4]); -- {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.