How to use part of sql query in the same query? - mysql

I have this query to get information from two tables:
SELECT u.username, u.id,
SUM(t.result = 1) AS winnings,
SUM(t.result = 2) AS loses
FROM users u
LEFT JOIN tahminler t ON u.id = t.user_id
GROUP BY u.id
I want to get comments_no for each user from another table; something like this:
SELECT u.username, u.id,
SUM(t.result = 1) AS winnings,
SUM(t.result = 2) AS loses,
f1.comments_no
FROM users u
LEFT JOIN tahminler t ON u.id = t.user_id
INNER JOIN (select count(distinct match_static_id) as comments_no,user_id from comments where user_id = "here is my problem")
GROUP BY u.id
Is it possible to but the value of u.id in the where user_id = u.id.
Briefly How to get the comments_no for each user in my query.?

Use a GROUP BY in the sub query:-
SELECT u.username, u.id,
SUM(t.result = 1) AS winnings,
SUM(t.result = 2) AS loses,
f1.comments_no
FROM users u
LEFT JOIN tahminler t ON u.id = t.user_id
INNER JOIN (select user_id, count(distinct match_static_id) as comments_no from comments GROUP BY user_id) f1
ON u.id = f1.user_id
GROUP BY u.id

Related

Where condition not working on MySQL union 2 tables

Sorted!!!
I have 2 tables, One table have person in charge for subscription. Second table have product users for each subscription and their details. I union both tables in mysql and query working 100% fine but when i try to filter records using where condition it return all the records without filtering.
Below you can find my query!
SELECT subscription_products.subscription_id, users.id, users.full_name,
users.company, users.job, users.birthday, users.gender,
users.nric, users.passport_number, users.phone_country_code,
users.phone_number, users.handphone_country_code, users.handphone_number,
users.email, users.nationality, wallets.current_amount,
users.created_at, users.updated_at
FROM subscription_product_users
LEFT JOIN subscription_products
ON subscription_product_users.subscription_product_id = subscription_products.id
LEFT JOIN users
ON subscription_product_users.user_id = users.id
LEFT JOIN wallets
ON users.id = wallets.user_id
UNION
SELECT person_in_charge.subscription_id, person_in_charge.user_id,
users.full_name,
users.company, users.job, users.birthday, users.gender,
users.nric, users.passport_number, users.phone_country_code,
users.phone_number, users.handphone_country_code,
users.handphone_number, users.email, users.nationality, wallets.current_amount,
users.created_at, users.updated_at
FROM person_in_charge
LEFT JOIN users
ON person_in_charge.user_id = users.id
LEFT JOIN wallets
ON person_in_charge.user_id = wallets.user_id
where subscription_id = '1378'
Can someone helps me?
Try to wrap it and it work
SELECT * FROM
(SELECT subscription_products.subscription_id, users.id, users.full_name,
users.company, users.job, users.birthday, users.gender,
users.nric, users.passport_number, users.phone_country_code,
users.phone_number, users.handphone_country_code, users.handphone_number,
users.email, users.nationality, wallets.current_amount,
users.created_at, users.updated_at
FROM subscription_product_users
LEFT JOIN subscription_products
ON subscription_product_users.subscription_product_id = subscription_products.id
LEFT JOIN users
ON subscription_product_users.user_id = users.id
LEFT JOIN wallets
ON users.id = wallets.user_id
UNION
SELECT person_in_charge.subscription_id, person_in_charge.user_id,
users.full_name,
users.company, users.job, users.birthday, users.gender,
users.nric, users.passport_number, users.phone_country_code,
users.phone_number, users.handphone_country_code,
users.handphone_number, users.email, users.nationality, wallets.current_amount,
users.created_at, users.updated_at
FROM person_in_charge
LEFT JOIN users
ON person_in_charge.user_id = users.id
LEFT JOIN wallets
ON person_in_charge.user_id = wallets.user_id)
as tempTable
where subscription_id = '1378'
Add the filter in both the queries, also I have used UNION ALL instead of UNION to have better performance. If your query will return duplicates and you want to avoid it, then replace it with UNION
You need to start using Alias in queries like this.
SELECT sp.subscription_id,
u.id,
u.full_name,
u.company,
u.job,
u.birthday,
u.gender,
u.nric,
u.passport_number,
u.phone_country_code,
u.phone_number,
u.handphone_country_code,
u.handphone_number,
u.email,
u.nationality,
w.current_amount,
u.created_at,
u.updated_at
FROM subscription_product_users spu
INNER JOIN subscription_products sp
ON spu.subscription_product_id = sp.id
LEFT JOIN users u
ON spu.user_id = u.id
LEFT JOIN wallets w
ON u.id = w.user_id
WHERE sp.subscription_id = '1378'
UNION ALL
SELECT pic.subscription_id,
pic.user_id,
u.full_name,
u.company,
u.job,
u.birthday,
u.gender,
u.nric,
u.passport_number,
u.phone_country_code,
u.phone_number,
u.handphone_country_code,
u.handphone_number,
u.email,
u.nationality,
w.current_amount,
u.created_at,
u.updated_at
FROM person_in_charge pic
LEFT JOIN users u
ON pic.user_id = u.id
LEFT JOIN wallets w
ON pic.user_id = w.user_id
WHERE pic.subscription_id = '1378'
select * from
(
(select 1 as 'a')
union
(select 2 as 'a')
) as u
where
u.a=2

SQL - select for each user the total articles and the total article comments

I am trying to get for each user the total number of articles and for each article the total number of comments, something like this:
username | total_articles | total_comments
John Doe | 3 | 10
This is my SQL until now, I am using MySQL:
SELECT u.id, u.username, COUNT(a.id) AS total_articles, COUNT(c.id) AS total_comments FROM users u
LEFT JOIN articles a ON u.id = a.user_id
LEFT JOIN comments c ON a.id = c.article_id
GROUP BY u.id;
I tried to group by u.id, a.id, c.id at the same time but it's not working correctly.
Thanks.
In the first query there are all the articles by user, in the second all the comments joined by user
edited: use LEFT JOIN insted JOIN
SELECT id_total_articles, username, total_articles, total_comments
FROM
(
SELECT u.id as id_total_articles, u.username, COUNT(a.id) AS total_articles FROM users u
LEFT JOIN articles a ON u.id = a.user_id
GROUP BY u.id, u.username
) as AC
left join
(
SELECT u.id as id_total_comments, COUNT(c.id) AS total_comments FROM users u
LEFT JOIN comments c ON u.id = c.user_id
GROUP BY u.id, u.username
) as CC
ON AC.id_total_articles = CC.id_total_comments;
use u.id, u.username both column in group by
SELECT u.id, u.username, COUNT(a.id) AS total_articles,
COUNT(c.id) AS total_comments FROM users u
LEFT JOIN articles a ON u.id = a.user_id
LEFT JOIN comments c ON a.id = c.article_id
GROUP BY u.id, u.username
If what you want is the number of articles for a user, and the total number of comments on all the articles of the user - then this is your query:
SELECT
u.id,
u.username,
COUNT(DISTINCT a.id) AS total_articles,
COUNT(c.id) AS total_comments
FROM users u
LEFT JOIN articles a
ON u.id = a.user_id
LEFT JOIN comments c
ON a.id = c.article_id
GROUP BY
u.id,
u.username;
But - if you are looking for the number of comments (just a thought here) of the user - then you want to join the comments table on the user id, and not the article id.
You are missing the u.username in the group by, also COUNT(a.id) must change into COUNT(distinct a.id):
SELECT u.id, u.username, COUNT(distinct a.id) AS total_articles, COUNT(c.id) AS total_comments FROM users u
LEFT JOIN articles a ON u.id = a.user_id
LEFT JOIN comments c ON a.id = c.article_id
GROUP BY u.id, u.username;
Update:
However, I guess that what you actually need is something other than your proposed query. You said that you need the total number of articles for each user and the total number of comment for each article. That means you need two separate queries:
SELECT a.id article_id , COUNT(c.id) AS total_comments
FROM articles a
LEFT JOIN comments c ON a.id = c.article_id
GROUP BY a.id
SELECT u.id, u.username, COUNT(distinct a.id) AS total_articles
FROM users u
LEFT JOIN articles a ON u.id = a.user_id
GROUP BY u.id, u.username;
You are aggregating along related dimensions and getting overcounting.
One approach is to use multiple aggregations:
SELECT u.id, u.username, COUNT(a.id) AS total_articles,
SUM(c.num_comments) AS total_comments
FROM users u LEFT JOIN
articles a
ON a.user_id = a.id LEFT JOIN
(SELECT c.article_id, COUNT(c.id) as num_comments
FROM comments c
GROUP BY c.article_id
) c
ON a.id = c.article_id
GROUP BY u.id, u.username;

MySQL: Needing to return top 3 Users with the most votes. Results wanted in one column from the SUM of two subqueries. Java/Spring MVC

I have a Spring MVC blog with functionality for Post and Comment voting. I want to return the top 3 users based on number of votes they've received on all their posts and comments.
tables:
users u [id, username]
posts p [id, u.id]
comments c [id, p.id, u.id]
post_votes pv [p.id, u.id, type (1 or -1)]
comment_votes cv [c.id, u.id, type (1 or -1)]
The following statement gives me total votes per user by querying two separate voting tables and then adding the totals together:
SELECT
(SELECT SUM(type)
FROM posts_votes pv
JOIN posts p ON p.id = pv.post_id
JOIN users u ON u.id = p.user_id
WHERE u.id LIKE ?1)
+
(SELECT SUM(type)
FROM comments_votes cv
JOIN comments c ON c.id = cv.comment_id
JOIN users u ON u.id = c.user_id
WHERE u.id LIKE ?1)
That works fine with a WHERE clause per user id... But now I'm trying to find just the top 3 users that have the most votes and I'm having too much difficulty. This is what I have so far:
SELECT u.id, u.username, IFNULL(SUM(pv.type), 0) AS totalPostVotes
FROM posts_votes pv
JOIN posts p ON p.id = pv.post_id
JOIN users u ON u.id = p.user_id
GROUP BY u.id ORDER BY totalPostVotes DESC LIMIT 3
That above statement works by itself giving me: u.id, u.username, and totalPostVote in descending order. So does the one below for comments:
SELECT u.id, u.username, IFNULL(SUM(cv.type), 0) AS totalCommentVotes
FROM comment_votes cv
JOIN comments c ON c.id = cv.comment_id
JOIN users u ON u.id = c.user_id
GROUP BY u.id ORDER BY totalCommentVotes DESC LIMIT 3
Great! But I want that third column SUM result to be essentially "totalVotes" and contain the sum of both of those subqueries. Then I'll GROUP BY u.id ORDER BY totalVotes DESC LIMIT 3.
Something like this:
SELECT u.id, u.username, SUM(
(SELECT IFNULL(SUM(pv.type), 0) AS totalPostVotes
FROM posts_votes pv
JOIN posts p ON p.id = pv.post_id
JOIN users u ON u.id = p.user_id
GROUP BY u.id ORDER BY totalPostVotes DESC LIMIT 1)
+
(SELECT IFNULL(SUM(cv.type), 0) AS totalCommentVotes
FROM comments_votes cv
JOIN comments c ON c.id = cv.comment_id
JOIN users u ON u.id = c.user_id
GROUP BY u.id ORDER BY totalCommentVotes DESC LIMIT 1))
AS totalVotes from users u
GROUP BY u.id, u.username ORDER BY totalVotes DESC LIMIT 3
id | username | totalVotes
2 user2 11
1 user1 11
29 user29 11
What's happening is the result of totalVotes is indeed the correct vote count, 11, for the "top" user, but none of those users are the real top user, and the correct vote is being repeated 3 times in the guise of other users. I'm not even sure how users are being sorted at that point because they're not in an order I recognize.
The subqueries work separately (they give me the correct user) when I add SELECT "u.id, u.username " IFNULL(SUM()) but then if I run the whole block, I get the error "Operand should contain 1 column(s)" So I delete them and revert to only SELECT IFNULL(SUM())
I'm also noticing the subqueries are only allowed LIMIT 1. How would I get the top 3, then? Should I do a UNION somewhere or is "+" sufficient? This is rather confusing. Can someone please help me with this? Any help is appreciated. Thanks in advance!
Updated code, thank you Peter:
SELECT
u.username,
pv_sum.total AS postTotal,
cv_sum.total AS commentTotal,
IFNULL(pv_sum.total, 0) + IFNULL(cv_sum.total, 0) as totalVotes
FROM users u
LEFT JOIN (
SELECT p.user_id, IFNULL(SUM(pv.type), 0) AS total
FROM posts p
JOIN posts_votes pv ON pv.post_id = p.id
GROUP BY p.user_id
) pv_sum ON pv_sum.user_id = u.id
LEFT JOIN (
SELECT c.user_id, IFNULL(SUM(cv.type), 0) AS total
FROM comments c
JOIN comments_votes cv ON cv.comment_id = c.id
GROUP BY c.user_id
) cv_sum ON cv_sum.user_id = u.id
GROUP BY u.username, postTotal, commentTotal
ORDER BY totalVotes DESC LIMIT 3;
Don't place your subqueries in your SELECT-part, but join them on the users-table:
SELECT
u.username,
pv_sum.total AS postTotal,
cv_sum.total as commentTotal,
IFNULL(pv_sum.total, 0) + IFNULL(cv_sum.total, 0) as totalVotes
FROM users u
LEFT JOIN (
SELECT p.user_id, IFNULL(SUM(pv.type), 0) AS total
FROM posts p
JOIN post_votes pv ON pv.post_id = p.id
GROUP BY p.user_id
) pv_sum ON pv_sum.user_id = u.id
LEFT JOIN (
SELECT c.user_id, IFNULL(SUM(cv.type), 0) AS total
FROM comments c
JOIN comment_votes cv ON cv.comment_id = c.id
GROUP BY c.user_id
) cv_sum ON cv_sum.user_id = u.id
GROUP BY u.id
ORDER BY totalVotes DESC
LIMIT 3;
Fiddle: http://sqlfiddle.com/#!9/980cb2/11

How can I calculate the number of all rows when there are both LIMIT and JOIN clauses?

Here is my query:
select u.id, u.name,
(select count(*) from users where name = u.name) as total
from users u
where u.name = 'anything'
order by id
limit 1
As you know, my query returns 1 user which has anything name. And total contains the number of all users which have anything name. Ok all fine.
Now I want to do the same thing when there are three JOINs in the query. Please assume this:
select u.id, u.name, sum(r.reputation) rep
from users u
join reputation r on u.id = r.user_id
join posts_tags pt on r.post_id = pt.post_id
join tags t on pt.tag_id = t.id
where u.name = 'anything' and t.name = 'mytag'
group by u.id, u.name
order by rep desc, u.id
limit 1
Now I want to know, how can I implement total part in this ^ query?
Try this query ,hope this give you the right result.
select * , count(id) as total from (select u.id, u.name, sum(r.reputation) rep
from users u
join reputation r on u.id = r.user_id
join posts_tags pt on r.post_id = pt.post_id
join tags t on pt.tag_id = t.id
where u.name = 'anything' and t.name = 'mytag'
group by u.id, u.name
order by rep desc, u.id
limit 1 ) as result

Select Command Where a field must equal a value but another field can have 2 values

I have the following SQL query:
SELECT users.user_id,
users.first_name,
users.last_name,
roles.role,
roles.role_id,
users.username,
users.description,
users_vs_teams.team_id,
teams.team_name,
teams.status,
teams.notes
FROM teams
INNER JOIN users_vs_teams ON teams.team_id = users_vs_teams.team_id
RIGHT OUTER JOIN users ON users_vs_teams.user_id = users.user_id
INNER JOIN roles ON users.role_id = roles.role_id
WHERE( users.role_id = 3 ) AND ( teams.status = 'Completed' ) OR ( teams.status IS NULL )
I want to display only users with a role_id of 3 but team.status can be either Completed or NULL. However, this query displays all roles where teams.status is either Completed or NULL. Any help resolving this issue will be greatly appreciated.
First, I'm not sure if you need an outer join for this. Second, your problem seems to be parentheses in the WHERE clause:
SELECT u.user_id, u.first_name, u.last_name, r.role, r.role_id,
u.username, u.description, uvt.team_id,
t.team_name, t.status, t.notes
FROM teams t INNER JOIN
users_vs_teams uvt
ON t.team_id = uvt.team_id INNER JOIN
users u
ON uvt.user_id = u.user_id
roles r
ON u.role_id = r.role_id ON u
WHERE (u.role_id = 3) AND (t.status = 'Completed' OR t.status IS NULL)
Note that table aliases make the query easier to write and to read.
Remove the RIGHT OUTER JOIN and fix your parenthesis in your WHERE clause.
SELECT users.user_id,
users.first_name,
users.last_name,
roles.role,
roles.role_id,
users.username,
users.description,
users_vs_teams.team_id,
teams.team_name,
teams.status,
teams.notes
FROM teams
INNER JOIN users_vs_teams ON teams.team_id = users_vs_teams.team_id
INNER JOIN users ON users_vs_teams.user_id = users.user_id
INNER JOIN roles ON users.role_id = roles.role_id
WHERE( users.role_id = 3 ) AND ( teams.status = 'Completed' OR teams.status IS NULL)
you can also do something like this:
( teams.status = 'Completed' OR ISNULL(teams.status,'') = '')