Want to Create View as per Condition Fires After Parameter Form.

Question

Hi ..
I want to create a report from a view,and that view would create after parameter form of that
report.
Example..
I want to select max(sal) of each Dept.where employee hired between 1-jan-2007 and 31-jul-2007'
I want when i Passes dates in Parameter FOrm
a view i.e select empno,deptno,sal, from emp created.
that means that view contains only data about that certain period
SO in Report Query i can write
select deptno,max(sal) from vw_employee
group by deptno.
This is just an example....my real problem is very hard and only can be done by doing create a view as per given dates in Report Parameter Form.
Waiting for Reply
Regards
Danish Hayder

Answer 1

Wrong ideea.
You should have the parameters in the report's query:
select empno,deptno,sal, from emp where hired between :p_start_date and :p_end_date
Why do you want to create a view in the report, seeing that it's best to use parameters.
Moreover, think that the oracle user running the report would have to have the priviledges to create views, which may not be good security policy.
Still, if you insist on creating the view when running the report, then you'd better create the view from a stored procedure, that would receive as parameter the SQL select for creating the view.
So, you'd have the stored procedure:
proc_view(p_select in varchar2, p_view_name in varchar2) is
begin
execute immediate 'create or replace view '||p)view_name||' as '||p_select;
end;
You then would compose the select in the afterpform trigger and call the proc_view procedure.
Note that I did not allow proc_view to execute immediate any SQL one would pass, for that would be really dangerous. What if one would pass to the procedure executing dynamic SQL the following: 'drop table my_table cascade constraints'?