交集、并集和补集
更新时间：2019-10-09 16:52:19
本文为您介绍UNION、UNOIN ALL、UNION DISTINCT并集，INTERSECT、INTERSECT ALL、INTERSECT DISTINCT交集，EXCEPT、EXCEPT ALL、EXCEPT DISTINCT补集等SQL语法。
语法格式如下。
select_statement UNION ALL select_statement;
select_statement UNION [DISTINCT] select_statement;
select_statement INTERSECT ALL select_statement;
select_statement INTERSECT [DISTINCT] select_statement;
select_statement EXCEPT ALL select_statement;
select_statement EXCEPT [DISTINCT] select_statement;
select_statement MINUS AL