内连接总和SQL

Question

我一直在尝试使用内部联接进行SUM，但是它显示每个单元而不是将它们加在一起并仅在一个单元中显示，那我在哪里做错了？

SELECT SUM(trans) as 'Transactions',city as 'city' 
FROM account 
INNER JOIN branch 
ON branch.bID 
GROUP BY account.trans, branch.city;

Answer 1

删除Group by account.trans 。 由于您添加了account.trans, branch.city group by account.trans, branch.city将显示每个trans和city sum(trans) 。

如果要每个city sum(trans)则在group by单独添加branch.city

SELECT SUM(trans) as 'Transactions'
FROM account 
INNER JOIN branch 
ON branch.bID 
Group by branch.city;

Answer 2

使用以下查询将返回每个城市的总和

SELECT SUM(trans) as 'Transactions', branch.city as 'city' 
FROM account 
INNER JOIN branch 
ON branch.bID = account.bID
GROUP BY branch.city;