cursor expressions problem

[bibi]

when i use cursor expression i get a cell in the result grid that can be clicked and give me the cursor result, but once i click it , this cursor cell cannot be clicked again, it says the cursor is no longer valid. i need to run the query again to access it.
is it done to save resources (unwanted open cursor)?
the query is something like (t1 is the master table and t2 is the details table):

select f1 as id,
cursor(select f1
from t2
where t2.f1 = t1.f1) as details
from t1

 

[Marco Kalter]

The cursor is opened by oracle when you execute the select statement with the nested cursor. When you view a cursor result set, all records are fetched. As you probably know, you cannot fetch from a cursor again unless you open it again. This can only be accomplished by re-executing the original query.