JOIN sender ON backlog.senderid = sender.senderid
WHERE backlog.messageid >= $1
AND backlog.messageid <= (SELECT buffer.lastmsgid FROM buffer WHERE buffer.bufferid = $1)
JOIN sender ON backlog.senderid = sender.senderid
WHERE backlog.messageid >= $1
AND backlog.messageid <= (SELECT buffer.lastmsgid FROM buffer WHERE buffer.bufferid = $1)