SELECT a.date, IF(ROUND(old/new, 3),ROUND(old/new, 3),0.000) AS p FROM ( SELECT q.date, q.new, IF(q.old,q.old,0) AS old FROM ( SELECT q1.date, q1.new, q2.old FROM ( SELECT DISTINCT login.date, IF(num,num,0) AS new FROM login LEFT JOIN( ...