Question

我正在尝试使用余额，结果和收入返回帐户列表

Account            Transaction
-------            -----------
AccountID          TransactionID
BankName           AccountID
Locale             Amount
Status

这是我现在拥有的。有人可以解释我哪里错了吗？

select
    a.ACCOUNT_ID,
    a.BANK_NAME,
    a.LOCALE,
    a.STATUS,
    sum(t1.AMOUNT) as BALANCE,
    sum(t2.AMOUNT) as OUTCOME,
    sum(t3.AMOUNT) as INCOME
from ACCOUNT a
left join TRANSACTION t1 on t1.ACCOUNT_ID = a.ACCOUNT_ID
left join TRANSACTION t2 on t2.ACCOUNT_ID = a.ACCOUNT_ID and t2.AMOUNT < 0
left join TRANSACTION t3 on t3.ACCOUNT_ID = a.ACCOUNT_ID and t3.AMOUNT > 0
group by a.ACCOUNT_ID, a.BANK_NAME, a.LOCALE, a.[STATUS]

更新

根据以下评论更正了t2左连接语法。

我期待的输出有望从问题中显而易见。对于6个帐户，SQL应返回6个帐户及其帐户的余额，收入和结果。

我提供的SQL问题是数字错误！根据评论，我认为问题源于连接多次，这是错误地汇总金额。

Answer 1

由于你没有告诉我们what's going wrong（也就是说，除了描述你期望的行为之外你描述的行为），很难说在哪里，但有几种可能性。尼尔指出一个。另一个原因是，由于您在事务表上加入了三次，因此您将事务与事务配对并重复进行。相反，请一次加入事务表，并更改Amount列的总结。

Select
    a.ACCOUNT_ID,
    a.BANK_NAME,
    a.LOCALE,
    a.STATUS,
    sum(t.AMOUNT) as BALANCE,
    sum((t.AMOUNT < 0) * t.AMOUNT) As OUTGOING,
    sum((t.AMOUNT > 0) * t.AMOUNT) As INCOMING
From ACCOUNT a
Left Join TRANSACTION t On t.ACCOUNT_ID = a.ACCOUNT_ID
Group By a.ACCOUNT_ID, a.BANK_NAME, a.LOCALE, a.[STATUS]

您可以使用CASE表达式作为乘法的更具可读性的替代方法：

Select
    a.ACCOUNT_ID,
    a.BANK_NAME,
    a.LOCALE,
    a.[STATUS],
    sum(t.AMOUNT) As BALANCE,
    sum(CASE WHEN t.AMOUNT < 0 THEN t.AMOUNT ELSE 0 end) As OUTCOME,
    sum(CASE WHEN t.AMOUNT > 0 THEN t.AMOUNT ELSE 0 end) As INCOME
From ACCOUNT a
Left Join [TRANSACTION] t On t.ACCOUNT_ID = a.ACCOUNT_ID
Group By a.ACCOUNT_ID, a.BANK_NAME, a.LOCALE, a.[STATUS]

Answer 2

你的意思是：

select 
    a.ACCOUNT_ID, 
    a.BANK_NAME, 
    a.LOCALE, 
    a.STATUS, 
    sum(t1.AMOUNT) as BALANCE, 
    sum(CASE WHEN t2.AMOUNT < 0 THEN t2.Amount ELSE 0 END) as OUTCOME, 
    sum(CASE WHEN t3.AMOUNT > 0 THEN t3.Amount ELSE 0 END) as INCOME 
from 
    ACCOUNT a 
    left join TRANSACTION t1 on t1.ACCOUNT_ID = a.ACCOUNT_ID 
    left join TRANSACTION t2 on t2.ACCOUNT_ID = a.ACCOUNT_ID
    left join TRANSACTION t3 on t3.ACCOUNT_ID = a.ACCOUNT_ID
group by 
    a.ACCOUNT_ID, a.BANK_NAME, a.LOCALE, a.[STATUS]

Answer 3

我不确定为什么你需要多个连接。你不能简单地做一些事情：

Select
    a.ACCOUNT_ID
    , a.BANK_NAME
    , a.LOCALE
    , a.STATUS
    , Sum ( t.Amount ) As Balance
    , Sum( Case When t.Amount < 0 Then Amount End ) As Outcome
    , Sum( Case When t.Amount > 0 Then Amount End ) As Income
From ACCOUNT a
    Left Join TRANSACTION t 
        On t.ACCOUNT_ID = a.ACCOUNT_ID
Group By a.ACCOUNT_ID, a.BANK_NAME, a.LOCALE, a.[STATUS]

Answer 4

TRANSACTION t2的加入应该是 on t2 ，如on t2.ACCOUNT_ID = a.ACCOUNT_ID

如何在GROUP BY中的多个条件上汇总列

4 个答案: