for rec in ( select  department_id, department_name from table1)
  loop
  /*if rec.department_id falls in or exists in  list of geographical area ( area_cd from some table which is a result of 
  two or more table))*/ 
  then  
  <perform some action using rec.department_id >;
  end if;
  end loop;  

for rec in ( select  department_id, department_name from table1)
  loop

   if rec.department_id = '999' then ( this is not compared with resulset)
   < action A>
   end if;

   if rec.department_id = '005' then
   < action A>
   end if;

     
 
  /*if rec.department_id falls in or exists in  list of geographical area ( area_cd from some table which is a result of 
  two or more table))*/ 
  then  
  <perform  action A using rec.department_id >;
  end if;
  end loop;  

if rec.department_id = ANY (select a.area_cd from ... where ...) 

initialize v_flag as null
select  1 into v_flag from dual where rec.department_id = ANY (select a.area_cd from ... where ...) 
now if v_flag=1 then...
<action>

begin 
 select 1 into flag from dual ...
 <do something>
exception when no_data_found then null;
end;