两个表中值不匹配的行

Question

我有两个表T1：

+----+-----+--------------------+----------+
| ID | emp |     manager        |     proj |
+----+-----+--------------------+----------+
|  1 | Sam |     Tom            |       aa |
|  1 | Sam |     Tom            |       bb |
|  1 | Sam |     Tom            |       cc |
|  1 | Sam |     Tom            |       dd |
+----+-----+--------------------+----------+

表T2：

+--------+---------+--------+-----------+
| Course |  Type   | proj   | Category  |
+--------+---------+--------+-----------+
| XYZ    |     NEW |     aa |    a      |
| DWE    |     OLD |     bb |    b      |
| RTY    |     OLD |     ii |    c      |
| UIO    |     NEW |     gg |    d      |
+--------+---------+--------+-----------+

输出：

+-----------+-----+----------+--------+---------+---------+----------+
|    ID     | emp |  manager |  proj  | Course  |  Type   | Category |
+-----------+-----+----------+--------+---------+---------+----------+
|         1 | Sam |  Tom     |     ii |     RTY |     OLD |     c    |
|         1 | Sam |  Tom     |     gg |     UIO |     NEW |     d    |
+-----------+-----+----------+--------+---------+---------+----------+

我有一个常见的col proj，表1由emp完成，而table2由emp完成，没有由emp完成，带有附加字段。我想从table2中获取所有不匹配的行，但具有上述表1中的属性。有人可以帮助执行SQL查询吗？

Answer 1

尝试

with a as (
select T2.* from T1 right join T2 
on T1.proj=T2.proj
where T1.proj is null) ,

 b as (select T1.id, T1.emp, t1.manager from T1 left join T2 
on T1.proj=T2.proj
group by T1.id, T1.emp, t1.manager,T2.proj
having T2.proj is null)

select * from a cross join b

Answer 2

select e.ID, e.emp, e.manager, t2.proj, t2.Course, t2.Type as Name, t2.Category
from t2
cross join (select distinct ID, emp, manager from T1) e
where not exists(select * from t1 where t1.prog=t2.proj)

Answer 3

选择tbl.ID，tbl.emp，tbl.manager，t2.proj，t2.Course，t2.Type作为Name，t2.Category
从 （ 选择t2.ID，t2.emp，t2.manager 从表2 t2 不存在的地方（从表1 t1中选择1，其中t1.proj = t2.proj） ）tbl 交叉应用表1 t1