Oracle中集合操作符

  下面是Oracle中集合操作符实例

     (1)Union all

1 --Union all 操作符
2 select a.product_id, a.product_type_id, a.name
3   from products a
4 union all
5 select b.prd_id, b.prd_type_id, b.name 
6  from more_products b 
7  order by 1

(2)Uinon 操作符

1 --Union 操作符
2 select a.product_id, a.product_type_id, a.name
3   from products a
4 union 
5 select b.prd_id, b.prd_type_id, b.name 
6  from more_products b 

(3)Intersect操作符

1 --Intersect 操作符
2 select a.product_id, a.product_type_id, a.name
3   from products a
4 intersect
5 select b.prd_id, b.prd_type_id, b.name 
6  from more_products b 

(4)Minus操作符

1 --Minus 操作符 A - B = A - (A INTERSECT B)
2 select a.product_id, a.product_type_id, a.name
3   from products a
4 minus
5 select b.prd_id, b.prd_type_id, b.name 
6  from more_products b 

 

posted @ 2012-11-03 21:05  原想  阅读(1588)  评论(0编辑  收藏  举报