MYSQL ukendt klausul join-kolonne i næste join

Prøv det sådan her, jeg har ikke noget skema til at teste det selv, men jeg føler, at det burde virke (eller sådan noget)

SELECT * FROM questions, connections
LEFT JOIN answers ON (questions.id = answers.id AND
                     connections.username2 = answers.username)
where connections.username1 = 'mikha';

til sidst som dette

SELECT * FROM questions
LEFT JOIN answers ON (questions.id = answers.id)
LEFT JOIN connections ON (connections.username2 = answers.username)
where connections.username1 = 'mikha';

EDIT:Jeg fandt dette i dokumentationen

Så for dit tilfælde kan det være

SELECT * FROM questions  
LEFT JOIN connections
LEFT JOIN answers ON (connections.username1 = 'mikha' AND questions.id = answers.id AND
                 connections.username2 = answers.username)