Question

I have the following situation on my database:

        id:   |   second id:  |  value 
Row 1:  1     |    1          |   123
Row 2:  1     |    2          |   234
Row 3:  1     |    3          |   456
Row 4:  2     |    1          |   987
Row 5:  2     |    2          |   876
Row 6:  2     |    3          |   765
Row 7:  3     |    1          |   345
Row 8:  3     |    2          |   678
Row 9:  3     |    3          |   543
Row 10: 4     |    1          |   345 
...

For each id I have 3 second ids, they are always 1,2 and 3.
What I need to do is get the average of this 3 values (contemplating the 3 valus for id) and get the average of them. I need to do this with a long table (I was wondering about creating a specific view to do this).

Any help will be welcome.

(Sorry for my question, but i really begginer on SQL Server)

Answer 1

Just use AVG and group by each id only.

SELECT id, AVG(value)
FROM MyTable
GROUP BY id