Question

I have a table called Comments that stores messages between two users, and the table structure looks like this:

id | from_id | to_id | comment | date

I want to query the data to only display the latest message between the two parties.
I’ve seen it done before.

I am using MYSQL.

Answer 1

Let’s say the two users id numbers are 1 and 2.

SELECT comment
FROM COMMENTS
WHERE (from_id = 1 OR from_id = 2)
AND (to_id = 1 OR to_id = 2)
ORDER BY date DESC
LIMIT 1;

If you really wanted to be pedantic, you could add this to the where clause:

AND NOT (from_id = to_id)

to prevent cases where they send a message to themselves showing up. This assumes it’s even possible for a user to send a message to them self in your system.