内联接:Select Table_a.a,Table_b.b from Table_a,Table_b where table_a.id = table_b.id 外联接: Select Table_a.a,Table_b.b from Table_a,Table_b where table_a.id(+) = table_b.id
外左联接:Select Table_a.a from Table_a a left outer join bwhere table_a.id = table_b.id 外右联接: Select Table_a.a from Table_a a right outer join where table_a.id = table_b.id 全连接: Select Table_a.a from Table_a a full outer join where table_a.id = table_b.id
a.id=b.id(+) ===> a left outer join b on a.id=b.id a.id(+)=b.id ===> a right outer join b on a.id=b.id
外联接: Select Table_a.a,Table_b.b from Table_a,Table_b where table_a.id(+) = table_b.id
外右联接: Select Table_a.a from Table_a a right outer join where table_a.id = table_b.id
全连接: Select Table_a.a from Table_a a full outer join where table_a.id = table_b.id
a.id(+)=b.id ===> a right outer join b on a.id=b.id
a.id(+)=b.id ===> b表内容全部显示