Question

This is my database layout:

• ID (int – unique primary key
• user (int) – foreign key for users I search by their name colum
• starttime (timestamp) – session start time
• endtime (timestamp) – session end time
• idletime (int) – idle time in minutes

For example I want to know how many minutes a specific player was online.

The following query works fine. I get about 3443 minutes.

SELECT user, 
       SUM(TIMESTAMPDIFF(MINUTE,starttime,endtime)-idletime) 
FROM gc_sessions 
WHERE user = 139

But if I want to do this with joins I get 8 by using the following query.

 SELECT name, 
        SUM(TIMESTAMPDIFF(MINUTE,starttime,endtime)-idletime) 
 FROM gc_sessions 
 JOIN gc_users ON gc_user.id = gc_sessions.id
WHERE name LIKE "variell"

What is wrong with my query?

Answer 1

Please try following query and tell me the result

SELECT `name`, SUM(TIMESTAMPDIFF(MINUTE,`starttime`,`endtime`)-`idletime`) 
    FROM `gc_sessions` inner JOIN `gc_users` ON 
    `gc_sessions`.`user` =`gc_users`.`id` WHERE gc_users.`name` LIKE "variell"