Question

how to insert only time in hh:mi in oracle and how to run select query by comparing time.

Explanation:
Let consider a doctor visit in hospital daily from 9AM to 11AM and 6PM to 8PM.
SO when we run a select query to search doctors who visit at 10AM on particular day.

Please give explanation with code.

Thanks in advance.

Answer 1

You just need basic date arithmetic, and the plain old date type.

CREATE TABLE doctor_visits (
    doctor_id    NUMBER NOT NULL,
    in_time      DATE NOT NULL,
    out_time     DATE NOT NULL
)
/

I presume you want to find doctors who were in the hospital at 10:00am, as opposed to doctors who visited exactly at 10AM

SELECT doctor_id FROM doctor_visits 
where in_time < trunc(in_time) + NUMTODSINTERVAL(10,'HOUR') 
AND out_time > trunc(in_time) + NUMTODSINTERVAL(10,'HOUR') ;

I haven’t considered the use case where in_time and out_time fall on different dates, i.e. say 11:00PM in and 2:00 am out.

OR IF you want to find a list of Doctors who visited the hospital exactly at 10:00AM then

SELECT doctor_id FROM doctor_visits where to_char(in_time,'HH:MI') = '10:00' ;

But that would be a very strange thing to query, as you really can’t be sure if some one visits exactly at that specific time.