explode_numbers(INT x)
Adding the _outer suffix after the function name of the table function changes the function behavior from non-outer to outer, and adds a row of Null data when the table function generates 0 rows of data.
mysql> select e1 from (select 1 k1) as t lateral view explode_numbers(0) tmp1 as e1; Empty set mysql> select e1 from (select 1 k1) as t lateral view explode_numbers_outer(0) tmp1 as e1; +------+ | e1 | +------+ | NULL | +------+
outer