oracle中union union all minus intersect

1、数据库A表和B表的结构是一样的，怎么把A中的数据全部复制到B重，而且要去重复.
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    去除重复：select * from a minus select * from b;
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    插入：insert into b (select * from a minus select * from b);

 或：insert into b (select * from a where a.id !=all(select id from b));