我有病人表,病人名称和有病人,保险的insurance_cover表。
我需要显示有保险和没有保险的病人,病人人数和保险总数,如果不使用联接,我该怎么做呢?
SELECT 'WITH INSURANCE' AS '',PATIENTNUM, PATIENTSURNAME
from PATIENT where PATIENTNUM
IN(select PATIENTNUM from INSURANCE_COVER)
UNION
SELECT 'WITHOUT INSURANCE' AS '',PATIENTNUM, PATI