带JOIN的MySQL WHERE子句

Question

I've got a SQL query which joins columns from three different tables and works fine. I only want this query to run if Room_ID is in an array I've got. The two queries work fine separately but I can't get them working together. This is what I'd like to run, if this condition is met:

SELECT message.Message, message.Period, message.Date, teacher.Firstname, teacher.Lastname, rooms.Room_ID, rooms.Description
FROM message JOIN
teacher
ON teacher.Teacher_ID = message.Teacher_ID JOIN
rooms
ON message.Room_ID = rooms.Room_ID

And this is the condition:

WHERE message.Room_ID IN myArray

I've tried brackets and putting the WHERE clause in different places but to no avail.

Answer 1

You could try this:

Say, $array is your array.

$sql = "SELECT message.Message, message.Period, message.Date, teacher.Firstname, teacher.Lastname, rooms.Room_ID, rooms.Description
FROM message LEFT JOIN teacher ON teacher.Teacher_ID = message.Teacher_ID LEFT JOIN rooms ON message.Room_ID = rooms.Room_ID WHERE message.Room_ID IN ".$array;

Hope this helps.

Peace! xD

Answer 2

$sql = "
    SELECT message.Message, message.Period, message.Date, teacher.Firstname, teacher.Lastname, rooms.Room_ID, rooms.Description
    FROM message 
    LEFT JOIN teacher ON teacher.Teacher_ID = message.Teacher_ID 
    LEFT JOIN rooms ON message.Room_ID = rooms.Room_ID 
    WHERE message.Room_ID IN (".implode(",", $myArray).")";