Question

I have the following tables (and example values):

**user:** user_id (1, 2, 3) username (john33, reddiamond...) password (pass1, pass2...)  **session:** session_id (4,5, 6) user_id (1, 2, 3)  **activity** activity_id (1, 2) name (running, walking...)  **user_activity** user_activity_id (1, 2, 3, 4, 5) session_id (4, 5) activity_id (1, 2) 

All columns with the same name are related. In the table user_activity there are rows which describe what is the session’s activity and the activity refers to users.

However I would like to get the table which describes what the user is currently doing:

**result** username(john33) activity.name(walking) 

What is the SQL statement that gets the result table?

(I’m using MSSQL).

Answer 1

SELECT u.username, a.name FROM user_activity ua INNER JOIN session s ON ua.session_id = s.session_id INNER JOIN user u ON s.user_id = u.user_id INNER JOIN activity a ON ua.activity_id = a.activity_id