retrive data from last 6 minths

[vegad]

hii have one more qus for u..Qus ; 2 Display the surname and telephone number of all patient who were admitted in the last 6 months who did not receive an operation.for this qus. i have two table one is ' patient_visit' and other one is 'operation'patient_visit <patient#,DOAdmission, DODischarge,Ward_Id>operation<operation#, Op_date, Op_type, Patient#, DOAdmission, Time_slot, theatre#>i want to find out that a patient who were admitted but not receive an operation from last 6 months.give me your idea...about that qus....and code reference also.....thanks waiting for u reply.....ok....bye

[Guest wheel]

SELECT * FROM PATIENT_VISIT WHERETO_CHAR(DOADMISSION,'DD-MON-YYYY') >TO_CHAR(ADD_MONTHS(DOADMISSION,-6),'DD-MON-YYYY')AND PATIENT_NO NOT IN(SELECT PATIENT_NO FROM OPERATION);