instruction: when was last the heartrate of patient 030-52327 measured today?
response: SELECT vitalperiodic.observationtime FROM vitalperiodic WHERE vitalperiodic.patientunitstayid IN (SELECT patient.patientunitstayid FROM patient WHERE patient.patienthealthsystemstayid IN (SELECT patient.patienthealthsystemstayid FROM patient WHERE patient.uniquepid = '030-52327')) AND NOT vitalperiodic.heartrate IS NULL AND DATETIME(vitalperiodic.observationtime, 'start of day') = DATETIME(CURRENT_TIME(), 'start of day', '-0 day') ORDER BY vitalperiodic.observationtime DESC LIMIT 1