I am new in this field and I fall short in trying to solve what I want. In a table imported from excel I have the columns
<grado, docente, curso, Nota1, Nota2, Nota3, Nota4, Nota5> some fields belonging to the notes contain an "X", my concern goes this way, I would like to generate a query similar to what results from the following:
SELECT grado, docente, curso, AVG(Nota1), AVG(Nota2), AVG(Nota3), AVG(Nota4), AVG(Nota5) FROM tabla GROUP BY docente,curso
However, the average I need in each of the notes should not consider the fields that contain "X", my first option was to add to the previous query a
WHERE Nota1 <> "X" and so with all the notes but this also affects the average of the columns that do not have any "X" because it restricts the entire row.
How could I solve this problem? Thanks in advance.