带 CASE 语句的 GROUP BY

Question

I have a table jobs with the following structure

================================================
| userID  |   jobDate  |  cityID  |  totalCost |
================================================
| 1234    | 2016-04-01 |    1     |     200    |
| 1234    | 2016-04-21 |    1     |     800    |
| 1234    | 2016-08-03 |    1     |     2000   |
| 1234    | 2016-12-01 |    1     |     300    |
| 1234    | 2017-02-01 |    1     |     500    |
================================================

I want the month to be transposed into columns.

Expected Output:

========================================================
| userID | April 2016 | May 2016 | .... | January 2017 |
========================================================
|  1234  |    1000    |   0      | .... |     500      |
========================================================

My query:

 SELECT u.userID, u.userFullName, ci.cityName,
    CASE
        WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'April 2016' THEN GROUP_CONCAT(CONCAT(c.categoryName, ' ', s.supercategoryName))
        ELSE '-'
    END AS 'April 2016 Services',
    CASE
        WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'April 2016' THEN SUM(j.totalCost + j.discountReceived)
        ELSE 0
    END AS 'April 2016 Spends',

    CASE
        WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'May 2016' THEN GROUP_CONCAT(CONCAT(c.categoryName, ' ', s.supercategoryName))
        ELSE '-'
    END AS 'May 2016 Services',
    CASE
        WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'May 2016' THEN SUM(j.totalCost + j.discountReceived)
        ELSE 0
    END AS 'May 2016 Spends',

    CASE
        WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'June 2016' THEN GROUP_CONCAT(CONCAT(c.categoryName, ' ', s.supercategoryName))
        ELSE '-'
    END AS 'June 2016 Services',
    CASE
        WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'June 2016' THEN SUM(j.totalCost + j.discountReceived)
        ELSE 0
    END AS 'June 2016 Spends',

    CASE
        WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'July 2016' THEN GROUP_CONCAT(CONCAT(c.categoryName, ' ', s.supercategoryName))
        ELSE '-'
    END AS 'July 2016 Services',
    CASE
        WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'July 2016' THEN SUM(j.totalCost + j.discountReceived)
        ELSE 0
    END AS 'July 2016 Spends',

    CASE
        WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'August 2016' THEN GROUP_CONCAT(CONCAT(c.categoryName, ' ', s.supercategoryName))
        ELSE '-'
    END AS 'August 2016 Services',
    CASE
        WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'August 2016' THEN SUM(j.totalCost + j.discountReceived)
        ELSE 0
    END AS 'August 2016 Spends',

    CASE
        WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'September 2016' THEN GROUP_CONCAT(CONCAT(c.categoryName, ' ', s.supercategoryName))
        ELSE '-'
    END AS 'September 2016 Services',
    CASE
        WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'September 2016' THEN SUM(j.totalCost + j.discountReceived)
        ELSE 0
    END AS 'September 2016 Spends',

    CASE
        WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'October 2016' THEN GROUP_CONCAT(CONCAT(c.categoryName, ' ', s.supercategoryName))
        ELSE '-'
    END AS 'October 2016 Services',
    CASE
        WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'October 2016' THEN SUM(j.totalCost + j.discountReceived)
        ELSE 0
    END AS 'October 2016 Spends',

    CASE
        WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'November 2016' THEN GROUP_CONCAT(CONCAT(c.categoryName, ' ', s.supercategoryName))
        ELSE '-'
    END AS 'November 2016 Services',
    CASE
        WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'November 2016' THEN SUM(j.totalCost + j.discountReceived)
        ELSE 0
    END AS 'November 2016 Spends',

    CASE
        WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'December 2016' THEN GROUP_CONCAT(CONCAT(c.categoryName, ' ', s.supercategoryName))
        ELSE '-'
    END AS 'December 2016 Services',
    CASE
        WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'December 2016' THEN SUM(j.totalCost + j.discountReceived)
        ELSE 0
    END AS 'December 2016 Spends',

    CASE
        WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'January 2017' THEN GROUP_CONCAT(CONCAT(c.categoryName, ' ', s.supercategoryName))
        ELSE '-'
    END AS 'January 2017 Services',
    CASE
        WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'January 2017' THEN SUM(j.totalCost + j.discountReceived)
        ELSE 0
    END AS 'January 2017 Spends',

    CASE
        WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'February 2017' THEN GROUP_CONCAT(CONCAT(c.categoryName, ' ', s.supercategoryName))
        ELSE '-'
    END AS 'February 2017 Services',
    CASE
        WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'February 2017' THEN SUM(j.totalCost + j.discountReceived)
        ELSE 0
    END AS 'February 2017 Spends',

    CASE
        WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'March 2017' THEN GROUP_CONCAT(CONCAT(c.categoryName, ' ', s.supercategoryName))
        ELSE '-'
    END AS 'March 2017 Services',
    CASE
        WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'March 2017' THEN SUM(j.totalCost + j.discountReceived)
        ELSE 0
    END AS 'March 2017 Spends'
FROM jobs j
LEFT JOIN categories c ON c.categoryID = j.categoryID
LEFT JOIN supercategories s ON s.supercategoryID = c.supercategoryID
LEFT JOIN users u ON u.userID = j.userID
LEFT JOIN city ci ON ci.cityID = j.cityID
WHERE j.jobStatus = 'completed' AND
      DATE(j.jobDate) BETWEEN '2016-04-01' AND DATE(NOW())
GROUP BY u.userID

Query Output:

========================================================
| userID | April 2016 | May 2016 | .... | January 2017 |
========================================================
|  1234  |    1500    |   0      | .... |      0       |
========================================================

All the rows are getting transposed into the first occurrence column. If I add GROUP BY MONTHNAME(jobDate) then I get multiple rows per user. Can you help what can be wrong here?

Answer 1

you just forgot to put sum on the case , see the first two months, you must put sum since you have multiple records per month (you can see you have two rows during April 2016

     SELECT u.userID, u.userFullName, ci.cityName,
       GROUP_CONCAT(CASE WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'April 2016' THEN CONCAT(c.categoryName, ' ', s.supercategoryName)
        END) AS 'April 2016 Services',
        SUM(CASE WHEN CONCAT(MONTHNAME(j.jobDate), ' ', YEAR(j.jobDate)) = 'April 2016' THEN ROUND(j.totalCost + j.discountReceived)
            ELSE 0
        END) AS 'April 2016 Spends',
    FROM jobs j
    LEFT JOIN categories c ON c.categoryID = j.categoryID
    LEFT JOIN supercategories s ON s.supercategoryID = c.supercategoryID
    LEFT JOIN users u ON u.userID = j.userID
    LEFT JOIN city ci ON ci.cityID = j.cityID
    WHERE j.jobStatus = 'completed' AND
          DATE(j.jobDate) BETWEEN '2016-04-01' AND DATE(NOW())
    GROUP BY u.userID