Mysql left join with condition in right table

Question

I have been trying to solve this issue for a while, hope anyone help me. I am having two table, the first table is

Table Name : OnlineTest

Answer 1

Place the d.userid = 1 predicate in the ON clause:

select c.onlinetestid, d.userid, d.status 
from onlinetest c 
left join userstatus d on d.onlinetestid = c.onlinetestid and d.userid = 1
where c.category = 'English' 

This will return all rows from onlinetest, having columns of userstatus filled with nulls where predicate d.userid = 1 fails.

Answer 2

You can also use left outer Join as below :

SELECT        c.OnlineTestId, d.userId, d.status
FROM            OnlineTest AS c LEFT OUTER JOIN
                         UserStatus AS d ON d.onlineTestId = c.OnlineTestId AND d.userId = 1
WHERE        (c.category = 'English')