交集、並集和補集
更新時間：2019-10-09 16:52:19
本文爲您介紹UNION、UNOIN ALL、UNION DISTINCT並集，INTERSECT、INTERSECT ALL、INTERSECT DISTINCT交集，EXCEPT、EXCEPT ALL、EXCEPT DISTINCT補集等SQL語法。
語法格式如下。
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