Question

I have some tables like this:

USERS TABLE:
| id | created | active | fname | lname |

MESSAGES TABLE:
| id | userId| active | date | content |

I am trying to return some user information, along with the most recently added message for a given user.
Below is the structure of the results that I am rying to achieve:

| userId | userCreated | latestMessageDate| latestMessageContent |

The following query returns the user information:

SELECT 
user.id, 
user.created
FROM user
WHERE user.active = 1

… But how do I now attach the date of the latest message, along with the actual latest message?

I believe using an inner query is one such approach, but how do you write such a query??

Answer 1

SELECT u.fname, u.lname, m.id, m.userID, m.datem, m.content
FROM USERS AS u
LEFT JOIN ( SELECT id, userID, date, content
            FROM MESSAGES
            WHERE active
            ORDER BY date DESC) AS m
ON u.id = m.userId
WHERE u.active
    # AND u.id = {$int_user_id}
GROUP BY u.id