在單個表格上計算增量

Question

如何計算位於同一個表格中的兩組數據之間的添加，刪除和修改？這裏有一個例子：

drop table if exists people; 
create table people (job int, id int, name varchar(255)); 

insert into people values (1, 1, "Amy"); 
insert into people values (1, 2, "Bob"); 
insert into people values (1, 3, "Chris"); 

insert into people values (2, 1, "Amy"); 
insert into people values (2, 2, "Robert"); 
insert into people values (2, 4, "Dennis"); 

在這個例子中，Bob的名字變成了羅伯特，克里斯已被刪除，丹尼斯已添加。

到目前爲止，我可以得到補充：

select p2.* from people p1 
right join people p2 
on p1.job = 1 
and p2.job = 2 
and p1.id = p2.id 
where p2.job = 2 
and p1.id is null; 

，我可以得到的缺失：

select p1.* from people p1 
left join people p2 
on p1.job = 1 
and p2.job = 2 
and p1.id = p2.id 
where p1.job = 1 
and p2.id is null; 

但我不知道怎麼去修改。

有沒有更好的方法？

謝謝

Answer 1

我設法搞清楚了！

select * from people p1 
join people p2 
on p1.job = 1 
and p2.job = 2 
and p1.id = p2.id 
where p1.name != p2.name; 

最後並沒有那麼糟糕。

Answer 2

對於您的示例數據，這將返回改性：

select * from people p1 
join people p2 
on p1.job = 1 
and p2.job = 2 
and p1.id = p2.id   -- same id 
WHERE p1.name <> p2.name -- but different name