joining two tables based on recent logged in datetime

Question

I am working on MySql and have two tables login_users and login_timestamps

Table login_users keeps a record of user_id , name and address whereas table login_timestamps keeps a record of user_id and timestamp , this table adds a new entry each time user logs in, so for example if the user_id '1' logs in 10 times a day, this table will have 10 entries for user_id '1' for today.

Now I need to fetch user profiles based on their last logged in time.

for example if there are 3 users, the MySql query should give me 3 records with their latest logged in time.

The query I am using is

SELECT * FROM login_users LEFT JOIN login_timestamps ON login_users.user_id = login_timestamps.user_id ORDER BY login_timestamps.timestamp DESC

but this gives me all the previous logged in entries rather than the recent one only.

Answer 1

Of course you will get all logged in entries while you didnt specify when or what day or something , hete you need a where clause.

try that:

  SELECT * FROM login_users 
  LEFT JOIN login_timestamps ON login_users.user_id = login_timestamps.user_id 
  WHERE DATE(`timestamp`) = CURDATE()
  ORDER BY login_timestamps.timestamp DESC

this will give you entries for curent day. of course you can specify any condition you want.

EDIT: from your comment.

try that

  SELECT l.user_id, max(timestamp)  as lasttime 
  FROM login_users l
  LEFT JOIN login_timestamps lt ON l.user_id = lt.user_id 
  GROUP BY l.user_id
  ORDER BY lasttime DESC