Can a dynamic select stmt in a ref cursor be done?

Question

Hello all!
I have a form in which a user can select a number of checkboxes that coorespond to fields in a table. After checking the desired boxes, the user can then click on a button and a variable (v_query) in a "when button pressed" trigger is populated with the text of a sql query. The trouble is, I want to incorporate the code contained in v_query into the REF cursor OPEN statement where it is expecting a sql query. The idea here is that the cursor would loop through the table fetching rows based on the select statement variable (v_query) and write them to a file using TEXT_IO(See below code). First, can this be done? Second, is there a better way to do accomplish this?
DECLARE
TYPE t_cur IS REF CURSOR ; -- define t_cur as a type
c_cur t_cur ; -- define an actual variable of type t_cur
r_emp emp%ROWTYPE ; -- PL/SQL record to hold row
v_query VARCHAR2(2000) := 'SELECT * FROM emp' ; -- the query!
BEGIN
-- OPEN FILE
out_file := Text_IO.Fopen('C:\BACHELOR\TEST.txt', 'w');
OPEN c_cur FOR v_query ; -- v_query could contain any valid query
LOOP
FETCH c_cur INTO r_emp ; -- get first row from dataset
EXIT WHEN %NOTFOUND
--PRINT TO FILE 
          Text_IO.Put_line(out_file, r_emp);
          Text_IO.New_Line(out_file);
END LOOP;
CLOSE c_cur ; -- remember to close the cursor! ;)
END;

Answer 1

Hello all!
I have a form in which a user can select a number of checkboxes that coorespond to fields in a table. After checking the desired boxes, the user can then click on a button and a variable (v_query) in a "when button pressed" trigger is populated with the text of a sql query. The trouble is, I want to incorporate the code contained in v_query into the REF cursor OPEN statement where it is expecting a sql query. The idea here is that the cursor would loop through the table fetching rows based on the select statement variable (v_query) and write them to a file using TEXT_IO(See below code). First, can this be done? Second, is there a better way to do accomplish this?
DECLARE
TYPE t_cur IS REF CURSOR ; -- define t_cur as a type
c_cur t_cur ; -- define an actual variable of type t_cur
r_emp emp%ROWTYPE ; -- PL/SQL record to hold row
v_query VARCHAR2(2000) := 'SELECT * FROM emp' ; -- the query!
BEGIN
-- OPEN FILE
out_file := Text_IO.Fopen('C:\BACHELOR\TEST.txt', 'w');
OPEN c_cur FOR v_query ; -- v_query could contain any valid query
LOOP
FETCH c_cur INTO r_emp ; -- get first row from dataset
EXIT WHEN %NOTFOUND
--PRINT TO FILE 
          Text_IO.Put_line(out_file, r_emp);
          Text_IO.New_Line(out_file);
END LOOP;
CLOSE c_cur ; -- remember to close the cursor! ;)
END;