SELECT
pic2.nid, pic2.cid, FROM_UNIXTIME(pic2.timestamp) AS posttime, pic2.comment_number,
pis.name AS newstate,
(pic2.timestamp-pic.timestamp)/86400 AS time_since_last
FROM node n, project_issues pi, project_issue_comments pic, project_issue_comments pic2, project_issue_state pis
WHERE n.nid=pi.nid AND pi.nid = pic2.nid AND pic.comment_number = pic2.comment_number-1
  AND pic.nid=pic2.nid AND pic2.sid=pis.sid
  AND pic2.nid=502500 AND pic.sid=8;