ONEXT takes an array expression as an argument and returns the subscript of the element subsequent to the element specified by integer_value or array_bound, if that element is currently populated. If you specify an element subscript that is greater than or equal to the value of OLAST for the array, a NULL is returned. Also, if integer_value or array_bound is NULL, an error is returned.
If array_expr is a one-dimensional ARRAY type, ONEXT returns an unsigned INTEGER value. If array_expr is a multidimensional ARRAY type, ONEXT returns a new instance of the predefined ARRAY type ArrayVec, containing the subscript information. If the array is empty (all elements of the array are in an uninitialized state), then ONEXT returns NULL.
If array_expr is NULL, an error is returned.
The ONEXT method with one INTEGER argument is compatible with the Oracle NEXT method for one-dimensional ARRAY types.