Question

I have a data in my database

userid    module      course     total
  8      Biophysics     A          117
  8      BioPhysics     B           74
  8      BioPhysics     C          135

I need the output like

userid      module       Courses        grade   
 8        BioPhysics    Course A: 117    250
                        Course B: 134  
                        Course C: 35

Answer 1

What you’re trying to accomplish is called “PIVOTing” row data into separate columns, and it is a feature that is not supported by MySQL, but what you can do is fake it if you know beforehand the range of data you want to pivot into columns.

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You have a couple of options:

Your example has A, B, and C for course per userid -> module combination. Assuming the values in course can only be A, B, or C: you can do a conditional aggregation for each value like so:

  SELECT userid,
         module,
         MAX(CASE course WHEN 'A' THEN total END) AS A,
         MAX(CASE course WHEN 'B' THEN total END) AS B,
         MAX(CASE course WHEN 'C' THEN total END) AS C,
         SUM(total) AS grade
    FROM tbl
GROUP BY userid, 
         module 

You can add as many CASE aggregations as you need (for D, E, F, etc.). Keep in mind some userid -> module combinations may have NULL for some of the columns if, for instance, it did not contain a row with C for course.

But if you do not know the range of values beforehand (and perhaps there could be hundreds of different values for course, you can still get all of the data onto one row, but it wouldn’t be in separate columns – it would actually be one concatenated string in a single column. This is accomplished by using GROUP_CONCAT():

  SELECT userid,
         module,
         GROUP_CONCAT(CONCAT(course, ': ', total) SEPARATOR ' / ') AS coursetotals,
         SUM(total) AS grade
    FROM tbl
GROUP BY userid,
         module

And what this would do is output something like:

userid  |  module      |  coursetotals             |  grade
-------------------------------------------------------------
8       |  BioPhysics  |  A: 117 / B: 74 / C: 135  |  326

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Here is a SQL-Fiddle Demo for both options

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Edit: As per your comments and edited, here is the new solution:

SELECT 
    a.userid, 
    a.module, 
    CONCAT('Course ', course, ': ', total) AS Courses, 
    b.grade
FROM
    tbl a
INNER JOIN
(
    SELECT userid, module, SUM(total) AS grade
    FROM tbl 
    GROUP BY userid, module
) b ON a.userid = b.userid AND a.module = b.module