Question

我正在尝试创建一个查询，以获取基于月份的最近12个月的图表表示。经过大量阅读并在看完similar topic之后，我创建了一个看起来正确的查询，但错过了0个月的月份。举个例子，我在图表中看到了1 / 14,2 / 14,4 / 14，等等...... 3/14缺失了。

我的代码就是这个

SELECT *
FROM
    (SELECT DATE_FORMAT(now(), '%m/%y') AS Month
     UNION SELECT DATE_FORMAT(DATE_SUB(now(), INTERVAL 1 MONTH), '%m/%y')
     UNION SELECT DATE_FORMAT(DATE_SUB(now(), INTERVAL 2 MONTH), '%m/%y')
     UNION SELECT DATE_FORMAT(DATE_SUB(now(), INTERVAL 3 MONTH), '%m/%y')
     UNION SELECT DATE_FORMAT(DATE_SUB(now(), INTERVAL 4 MONTH), '%m/%y')
     UNION SELECT DATE_FORMAT(DATE_SUB(now(), INTERVAL 5 MONTH), '%m/%y')
     UNION SELECT DATE_FORMAT(DATE_SUB(now(), INTERVAL 6 MONTH), '%m/%y')
     UNION SELECT DATE_FORMAT(DATE_SUB(now(), INTERVAL 7 MONTH), '%m/%y')
     UNION SELECT DATE_FORMAT(DATE_SUB(now(), INTERVAL 8 MONTH), '%m/%y')
     UNION SELECT DATE_FORMAT(DATE_SUB(now(), INTERVAL 9 MONTH), '%m/%y')
     UNION SELECT DATE_FORMAT(DATE_SUB(now(), INTERVAL 10 MONTH), '%m/%y')
     UNION SELECT DATE_FORMAT(DATE_SUB(now(), INTERVAL 11 MONTH), '%m/%y')
    ) AS Months
LEFT JOIN
    (SELECT sum(expenses.price) AS ExpenseAmount,
            sum(payments.amount) AS PaymentsAmount,
            DATE_FORMAT(expenses.date_occurred,'%m/%y') AS Month,
            DATE_FORMAT(payments.date_occurred,'%m/%y') AS Montha
     FROM expenses,
          payments
     WHERE payments.user_id= 1
         AND payments.user_id=expenses.user_id
     GROUP BY MONTH(payments.date_occurred),
              YEAR(payments.date_occurred)
     ORDER BY payments.date_occurred ASC ) data ON Months.MONTH = data.Montha
ORDER BY data.Montha;

任何帮助都会很棒，因为这种查询对我来说太先进了： - ）

enter image description here

Answer 1

由于查询看起来应该为每个月生成一行，您是否可以检查查询输出，而不是图表生成的内容？我怀疑你有一个04/14的条目，但是该值是NULL而不是0.要纠正这个，你可以改变查询开始

SELECT Months.Month, 
    COALESCE(data.ExpenseAmount, 0) AS ExpenseAmount, 
    COALESCE(data.PaymentAmount, 0) AS PaymentAmount

COALESCE将为您提供0而不是NULL，其中没有与左连接匹配的行。

但是，您的查询还有其他问题。如果在同一个月有费用和付款，您只会获得行 - 请检查http://sqlfiddle.com/#!2/3f52a8/1，如果从一个表中删除部分数据，您就会看到问题。

这是一个可行的解决方案，可以为您提供所有月份，从两个表中总结数据，即使只有一个表存在。这可以通过将费用和付款作为单独的查询来处理，然后将它们连接在一起。

SELECT Months.Month, COALESCE(expensedata.ExpenseAmount, 0) AS ExpenseAmount, COALESCE(paymentdata.PaymentAmount, 0) AS PaymentAmount
FROM
    (SELECT DATE_FORMAT(now(), '%m/%y') AS Month
     UNION SELECT DATE_FORMAT(DATE_SUB(now(), INTERVAL 1 MONTH), '%m/%y')
     UNION SELECT DATE_FORMAT(DATE_SUB(now(), INTERVAL 2 MONTH), '%m/%y')
     UNION SELECT DATE_FORMAT(DATE_SUB(now(), INTERVAL 3 MONTH), '%m/%y')
     UNION SELECT DATE_FORMAT(DATE_SUB(now(), INTERVAL 4 MONTH), '%m/%y')
     UNION SELECT DATE_FORMAT(DATE_SUB(now(), INTERVAL 5 MONTH), '%m/%y')
     UNION SELECT DATE_FORMAT(DATE_SUB(now(), INTERVAL 6 MONTH), '%m/%y')
     UNION SELECT DATE_FORMAT(DATE_SUB(now(), INTERVAL 7 MONTH), '%m/%y')
     UNION SELECT DATE_FORMAT(DATE_SUB(now(), INTERVAL 8 MONTH), '%m/%y')
     UNION SELECT DATE_FORMAT(DATE_SUB(now(), INTERVAL 9 MONTH), '%m/%y')
     UNION SELECT DATE_FORMAT(DATE_SUB(now(), INTERVAL 10 MONTH), '%m/%y')
     UNION SELECT DATE_FORMAT(DATE_SUB(now(), INTERVAL 11 MONTH), '%m/%y')
    ) AS Months

LEFT JOIN 
  (SELECT SUM(price) AS ExpenseAmount, DATE_FORMAT(date_occurred,'%m/%y') AS Month
   FROM expenses 
   WHERE user_id = 1
   GROUP BY MONTH(date_occurred), YEAR(date_occurred)) expensedata ON Months.Month = expensedata.Month

LEFT JOIN 
  (SELECT SUM(amount) AS PaymentAmount, DATE_FORMAT(date_occurred,'%m/%y') AS Month
   FROM payments
   WHERE user_id = 1
   GROUP BY MONTH(date_occurred), YEAR(date_occurred)) paymentdata ON Months.Month = paymentdata.Month

ORDER BY Months.Month;

显示此工作的SQL小提琴：http://sqlfiddle.com/#!2/3f52a8/5

Answer 2

我认为你的问题是左连接。左边连接中的select语句的结果不包含任何0钱的结果...它看起来像你的

where payments.user_id = 1

是问题......

在以下链接中，您可以找到所有类型的联接的解释... http://blog.codinghorror.com/a-visual-explanation-of-sql-joins/

希望有所帮助

Answer 3

将ORDER BY data.Montha替换为ORDER BY Months.MONTH

数据中没有“3/14”.Montha。

过去12个月的Mysql总和

3 个答案: