instruction: i was wondering what patient 015-59552's minimum value of systemicmean on 03/09/2105 was?
response: SELECT MIN(vitalperiodic.systemicmean) FROM vitalperiodic WHERE vitalperiodic.patientunitstayid IN (SELECT patient.patientunitstayid FROM patient WHERE patient.patienthealthsystemstayid IN (SELECT patient.patienthealthsystemstayid FROM patient WHERE patient.uniquepid = '015-59552')) AND NOT vitalperiodic.systemicmean IS NULL AND STRFTIME('%y-%m-%d', vitalperiodic.observationtime) = '2105-03-09'