hello to all and thanks for help in advance
Below are my details:
--create table.
create table t02(
fname varchar2(10),
city varchar2(10),
country varchar2(5),
start_date date,
end_date date);
/
insert into t02 values('Tom','Boston','US','01-JAN-2001', '31-JUL-2001');
insert into t02 values('Tom','Nashua','US','01-AUG-2001', '31-DEC-2001');
insert into t02 values('Tom','New York','US','01-JAN-2002', '31-DEC-2002');
insert into t02 values('Tom','Mumbai','IND','01-JAN-2003', '31-DEC-2003');
insert into t02 values('Tom','Dallas','US','01-JAN-2004', '31-DEC-2004');
insert into t02 values('Tom','Austin','US','01-JUL-2004', '31-DEC-2006'); -- How can I check it? IT would not possible insert a row where date is inside others, each start_date have to be > of previous end date of prev row
/
commit;
/
select * from t02
order by start_date
check must be in a BEFORE trigger
Thanks