outer组合器

description

在table function的函数名后面添加_outer后缀使得函数行为从non-outer变为outer,在表函数生成0行数据时添加一行Null数据。

example

1. mysql> select e1 from (select 1 k1) as t lateral view explode_numbers(0) tmp1 as e1;
2. Empty set

4. mysql> select e1 from (select 1 k1) as t lateral view explode_numbers_outer(0) tmp1 as e1;
5. +------+
6. | e1   |
7. +------+
8. | NULL |
9. +------+

keywords

1. outer