Using mysql LEFT Join DESC order is not working - mysql

Question

Here i have two table,i have to join these two table and i have to get the plan details, i tried but is not happening, here is my code
user_info
id fullName
1 Arun
2 Sarvan
user_active_plan
id userId planName
1 1 Free Plan
2 1 Cool Plan
3 2 Free Plan
contact_property
id userId contactProperty
1 1 A
2 1 B
3 2 C
Here user_info(tablename) id (column name) i am using foreign key of user_active_plan(table name) userId(column name)
I want get the latest plan based on userId,So i am using desc order , but it is not coming expected results:
$sql = "SELECT a.fullName,b.*FROM user_info a LEFT JOIN user_active_plan b ON a.id = b.userId GROUP BY b.userId ORDER BY id DESC";
$result = $this->GetJoinRecord($sql);
print_r($result);
I am getting the following incorrect results:
Array
(
[0] => Array
(
[fullName] => Sarvan
[id] => 3
[userId] => 2
[planName] => Free Plan
)
[1] => Array
(
[fullName] => Arun
[id] => 1
[userId] => 1
[planName] => Free Plan
)
)
)
I was expecting the following:
Array
(
[0] => Array
(
[fullName] => Sarvan
[id] => 3
[userId] => 2
[planName] => Free Plan
)
[1] => Array
(
[fullName] => Arun
[id] => 2
[userId] => 1
[planName] => Coll Plan
)
)
)
Updated Expected Answer
Array
(
[0] => Array
(
[userId] => 1
[fullName] => Arun
[planId] => 2
[planName] => Cool Plan
[contactCount] => 2
)
[1] => Array
(
[userId] => 2
[fullName] => Sarvan
[planId] => 3
[planName] => Free Pla1
[contactCount] => 1
)
)

Answer 1

You can get the latest plan with a simple subquery, no need for grouping. The count of contacts can be done with a simple grouping:
SELECT u.id AS userId, u.fullName, p.id AS planId, p.planName, COUNT(c.userId) AS contactCount
FROM user_info u
LEFT JOIN user_active_plan p ON u.id = p.userId
LEFT JOIN contact_property c ON u.id = c.userId
WHERE p.id = (SELECT id
FROM user_active_plan
WHERE userId = u.id
ORDER BY id DESC
LIMIT 1)
GROUP BY c.userId;
You can also move the condition from the WHERE clause to the join:
SELECT u.id AS userId, u.fullName, p.id AS planId, p.planName, COUNT(c.userId) AS contactCount
FROM user_info u
LEFT JOIN user_active_plan p ON u.id = p.userId
AND p.id = (SELECT id
FROM user_active_plan
WHERE userId = u.id
ORDER BY id DESC
LIMIT 1)
LEFT JOIN contact_property c ON u.id = c.userId
GROUP BY c.userId;