Question

I know questions like this have been asked before, but I’m not sure how I can apply it to my code. I have two tables. I have an entry table that stores entries like this:

id | name | description
1    Test   Test entry

In the other table, I have a rating table like this:

id | entryid | rating
1  | 1       | 1
2  | 1       | -1

I want to list all the entries in the first table, but order them by the total rating. So, in this example, Entry #1 would have a rating of 0, because 1 + -1 = 0. Is there a way that I can do this with a query?

Answer 1

Check this SQLFIDDLE DEMO. You just need to use Sum to count all ratings per each entryID.

Query:

select r.entryid, sum(r.rating)
from ratings r
group by r.entryid
;

Result:

ENTRYID     SUM(R.RATING)
1           -1
2           2

Final Query:

select e.id, e.name, sum(r.rating)
from entry e
left join 
ratings r
on r.entryid = e.id
group by e.id
;

Final Results:

ID  NAME    SUM(R.RATING)
1   Test1   -1
2   Test2   2