mysql select query help like in shown pictures
I have a table in mysql like shown below in p开发者_如何学Cicture 1:
Can you tell me how to make a select query which result will be like in picture 2
and to select faster:Assumes that you have a unique constraint on STUD_ID,CLASS,LESSON
SELECT STUD_ID,
CLASS,
MAX(CASE WHEN LESSON='MATH' THEN MARK END) AS MATH,
MAX(CASE WHEN LESSON='CHEM' THEN MARK END) AS CHEM,
...
AVG(MARK) AS `Avg`
GROUP BY STUD_ID, CLASS
(If you really need that ID
column that doesn't relate to any ids you can use the technique from here).
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