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

keywords

  1. outer