Question

我有两个表，每个表有两列

Table 1: UserID, UserName
Table 2: UserID, rate

费率列可以取值A或B.

是否可以列出由（num of As） - （num of Bs）

排序的用户名

基本上每个UserID可以有多个As和B，我想按照（#sn的数量减去B的数量）列出UserID

Answer 1

尝试使用：

SELECT t1.UserName, 
    (SUM(IF(t2.rate = 'A'), 1, 0) - SUM(IF(t2.rate = 'B'), 1, 0)) as temp 
FROM table1 t1 INNER JOIN table2 t2 
ON t1.UserID = t2.UserID 
GROUP BY t1.UserID 
ORDER BY temp;

Answer 2

我认为这是您正在寻找的查询：

SELECT T1.UserID
      ,COUNT(T2A.rate) - COUNT(T2B.rate) AS [rateDiff]
FROM Table1 T1
LEFT OUTER JOIN Table2 T2A ON T2A.UserID = T1.UserID
                            AND T2A.rate = 'A'
LEFT OUTER JOIN Table2 T2B ON T2B.UserID = T1.UserID
                            AND T2B.rate = 'B'
GROUP BY T1.UserID
ORDER BY COUNT(T2A.rate) - COUNT(T2B.rate)

希望这会有所帮助，告诉我结果是不是你期望的结果。

按两列列出表

2 个答案: