Multiple LEFT JOINS with Multiple COUNT() count all colum - php

Question

I have 4 tables.
table groups
| ID | NAME |
1 Premium
2 Silver
table user
| ID | group_id | NAME |
1 1 Serhan
2 2 Farhat
table user_statistics
| ID | user_id | TYPE |
1 1 1
2 2 0
table votes
| ID | user_id | VOTE |
1 1 1
2 2 0
3 1 0
I created an sql query to retrieve user details who is in same group. It's worked! Then I want to retrieve any of vote that have been voted to user in groups. I want to count the vote. So basically I've made this sql query.
global $conn;
$res_groups = array();
$stmt = $conn->prepare("
SELECT * FROM groups
");
$stmt->execute();
$stmt->setFetchMode(PDO::FETCH_ASSOC);
while ($group = $stmt->fetch()){
$groups = array();
$groups['id'] = $group['id'];
$groups['name'] = $group['name'];
$user_arr = array();
$stmts = $conn->prepare('
SELECT l.*,
(SELECT MAX(ls.date) from user_statistics ls WHERE ls.user_id = l.id GROUP BY ls.user_id) as ls_date,
(SELECT SUM(IF(ls.type="0", ls.type, 0)) FROM user_statistics ls WHERE ls.user_id = l.id GROUP BY ls.user_id) as ls_us,
(SELECT SUM(IF(ls.type="1", ls.type, 0)) FROM user_statistics ls WHERE ls.user_id = l.id GROUP BY ls.user_id) as ls_uk,
(SELECT COUNT(*) FROM user_statistics WHERE type="1" AND ls.user_id = l.id GROUP BY ls.user_id) as totals,
(SELECT COUNT(*) FROM votes v WHERE v.vote=0 AND confirm=0 AND v.user_id = l.id) as badvote,
(SELECT COUNT(*) FROM votes v WHERE v.vote=1 AND confirm=0 AND v.user_id = l.id) as goodvote
FROM user l
LEFT JOIN
user_statistics ls on l.id = ls.user_id
LEFT JOIN votes v on v.user_id = l.id
WHERE l.group_id = '.$groups['id'].' AND status = 1
GROUP BY l.id,ls.user_id
');
$stmts->execute();
$stmts->setFetchMode(PDO::FETCH_ASSOC);
while ($usr = $stmts->fetch()){
$totalvote=($usr['badvote']+$usr['goodvote']);
if($totalvote>0){
$badvote=bcdiv($usr['badvote']*100/$totalvote,1,2);
$goodvote=bcdiv($usr['goodvote']*100/$totalvote,1,2);
}else{
$badvote=0;
$goodvote=0;
}
$votes[] = array(
"count" => $usr['badvote'],
"percent" => $badvote
);
$votes[] = array(
"count" => $usr['goodvote'],
"percent" => $goodvote
);
$user_arr[] = array(
"id" => $usr['id'],
"group_id" => $usr['group_id'],
"name" => $usr['name'],
"votes_summary" => $votes
);
}
$groups['list'] = $user_arr;
$res_groups[] = $groups;
}
All code seems work unless one thing. The VOTE is always return to count all column in my database VOTES and apply the data to all of my user. What I want is to get how many vote that each user get based on vote type GOOD or BAD.
Any help will be nice.

Answer 1

Looking to your code you could refactor your query avoiding select subquery one for each row and using two subquery with group by in join.
You have also the same code for bad and good vote could be you need different code for obtain different values
SELECT l.*
, t1.ls_date
, t1.ls_us
, t1.ls_uk
, t2.totals
, t2.badvote
, t2.goodvote
FROM user l
INNER JOIN (
SELECT ls.user_id
, MAX(ls.date) ls_date
, SUM(IF(ls.type="0", ls.type, 0)) ls_us
, SUM(IF(ls.type="1", ls.type, 0)) ls_uk
from user_statistics ls
GROUP BY ls.user_id
) t1 on t1.user_id = l.id
LEFT JOIN (
SELECT v.user_id
, sum( case when type="1" then 1 else 0 end ) totals
/* these are the same */
, sum ( case when v.vote=1 AND confirm=0 then 1 else 0 END ) badvote
/* these are the same */
, sum ( case when v.vote=1 AND confirm=0 then 1 else 0 END ) goodvote
FROM votes v
) t2 ON t2.user_id = l.id
WHERE l.group_id = '.$groups['id'].'
AND status = 1
And you should avoid the use of PHP var in SQL (you are at risk for SQL injection). For this you should take a look at your db driver for prepared statement and binding value, or at least be sure you sanitize properly the php var content