so what's the maximum neutrophils value of patient 64519 in 07/2104?
select max(labevents.valuenum) from labevents where labevents.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 64519 ) and labevents.itemid in ( select d_labitems.itemid from d_labitems where d_labitems.label = 'neutrophils' ) and strftime('%y-%m',labevents.charttime) = '2104-07'