array_size (size, cardinality)
BIGINT size(ARRAY<T> arr) BIGINT array_size(ARRAY<T> arr) BIGINT cardinality(ARRAY<T> arr)
Returns the size of the array, returns NULL for NULL input.
mysql> select k1,k2,size(k2) from array_test; +------+-----------+------------+ | k1 | k2 | size(`k2`) | +------+-----------+------------+ | 1 | [1, 2, 3] | 3 | | 2 | [] | 0 | | 3 | NULL | NULL | +------+-----------+------------+ mysql> select k1,k2,array_size(k2) from array_test; +------+-----------+------------------+ | k1 | k2 | array_size(`k2`) | +------+-----------+------------------+ | 1 | [1, 2, 3] | 3 | | 2 | [] | 0 | | 3 | NULL | NULL | +------+-----------+------------------+ mysql> select k1,k2,cardinality(k2) from array_test; +------+-----------+-------------------+ | k1 | k2 | cardinality(`k2`) | +------+-----------+-------------------+ | 1 | [1, 2, 3] | 3 | | 2 | [] | 0 | | 3 | NULL | NULL | +------+-----------+-------------------+
ARRAY_SIZE, SIZE, CARDINALITY