Get total upvotes for each user for all his posts - mysql

Question

The database structure is as follows:
users
[id] [name] [etc...]
1 Echolot ...
2 AnotherUser ...
posts
[id] [user_id] [title] [etc...]
1 1 Post1 ...
2 1 Post2 ...
posts_upvotes
[id] [post_id] [user_id (user who voted)] [value (1 or 0 or -1)]
1 1 1 1
2 1 2 -1
3 2 1 1
4 2 2 1
I'm trying to get a list of all users and their total amount of upvotes sum(value)gathered by all their posts like so:
id: 1
name: Echolot
upvoteCount: 2
id: 2
name: AnotherUser
upvoteCount: 0
I have tried using the following query but without success, I get wrong values and not the right amount of results:
SELECT joinedUsers.id, joinedPosts.postCount, joinedPostsUpvotes.upvoteCount
FROM users joinedUsers
inner join (
SELECT user_id, id, count(id) as postCount
FROM posts
GROUP BY user_id, id
) joinedPosts on joinedPosts.user_id = joinedUsers.id
inner join (
SELECT post_id, sum(value) as upvoteCount
FROM posts_upvotes
GROUP BY post_id
) joinedPostsUpvotes on joinedPostsUpvotes.post_id = joinedPosts.id
GROUP BY joinedUsers.id, joinedPosts.postCount, joinedPostsUpvotes.upvoteCount
Thank you in advance for any hints or solutions.
EDIT: Added test data and expected results.

Answer 1

You don't need all those subqueries, you can just use a couple left join between user, post and post_upvotes:
SELECT t1.id, t1.name, count(distinct t2.id), sum(t3.value)
FROM users t1
LEFT JOIN
posts t2
ON t1.id = t2.user_id
LEFT JOIN
posts_upvotes t3
ON t2.id = t3.post_id
GROUP BY t1.id, t1.name
The use of left join instead of inner join ensures you that users with no posts or posts with no votes will be displayed as well.

Answer 2

I think this would do the trick for you:
SELECT u.id,
u.name,
COUNT(p.id)
SUM(pu.value)
FROM users AS u
JOIN posts AS p
ON u.id = p.user_id
JOIN posts_upvotes AS pu
ON p.id = pu.post_id
GROUP BY u.id,
u.name
If I am not missing something in your question.

Answer 3

I think it would be something like this if you want the count of the amount of times someone voted (not tested)
SELECT users.id, users.name, COUNT(posts_upvotes.id) as upvoteCount
FROM users
INNER JOIN posts_upvotes ON posts_upvotes.user_id = users.id
GROUP BY users.id
Or this if you want the sum of the value of the upvotes:
SELECT users.id, users.name, SUM(posts_upvotes.id) as upvoteSum
FROM users
INNER JOIN posts_upvotes ON posts_upvotes.user_id = users.id
GROUP BY users.id
Or in Laravel you could use the Query Builder: https://laravel.com/docs/5.4/queries
Something like this:
DB::table('users')
->join('posts_upvotes', 'users.id', '=', 'posts_upvotes.user_id'))
->groupBy('users.id')
->select('users.id', 'users.name', DB::raw('COUNT(posts_upvotes) as upvoteCount'))
->get();