Building report from PL/SQL cursor

Question

Hello,
is there any way to build APEX report using just PL/SQL cursor?
I don't have grant to SELECT from views or tables, but I can use some functions returning row types and cursors. I know I can use them to build table from scratch with htp.p etc., but it’s not very nice. I want to do it using APEX reporting with filtering and pagination functionality.
Is it possible?
Regards,
Przemek

Answer 1

Apologies for the delay, I was out of the office.
Below is a package serving as the basis for creating a view based on a pipelined function. The package is just a skeleton and will not compile in its current form, you will need to go through it filling in the blanks as described by the comments.
If you want some control over what rows are returned by the view from a larger result set, use the set_parameters function in the WHERE clause, E.G.:
select * from really_big_complicated_slow_view where 1 = view_pkg.set_parameters(something_that_reduces_the_view_result_set_size);
Or, a more concrete example:
select result_text from view_to_convert_to_csv where 1 = view_pkg.set_parameters(pi_table => 'my_table', pi_where = 'whatever');
In the spirit of full disclosure, I got the idea for using the "set_parameters" function in the view WHERE clause from a post or blog somewhere a couple of years ago but have lost track of who actually deserves the credit for the good idea.
-Tom
create or replace package demo_vw as
-- Package to serve as the basis for a view based on a function
-- Customize this record so that it represents a row from this view...
type row_type is record (
-- record fields here
type table_type is table of row_type;
-- This function is used in the DDL to define the view, for example:
-- create or replace view my_view (col1, col2, ..., colN) as
-- select * from table(my_view_vw.get_view);
function get_view
return table_type
pipelined;
-- Customize this function header to accept the parameters for this view, if
-- any. If this view does not require any parameters, the set_parameters
-- function may be deleted.
-- This function should always return 1 and is called as follows
-- select <whatever>
-- from my_view
-- where 1 = my_view_vw.set_parameters(p1, p2, p3, ..., pN);
function set_parameters (pi_whatever1 in whatever,
pi_whateverN in whatever)
return number;
end demo_vw;
show error package demo_vw
create or replace package body demo_vw as
-- Customize this list of private global variables to match the parameters
-- required by the view. These variables are set, reset, and validated by
-- set_parameters, reset_parameters, and valid_parameters respectively...
g_var1 whatever;
g_varN whatever;
function set_parameters (pi_whatever1 in whatever,
pi_whateverN in whatever)
return number
is
-- Customize this function header to accept the parameters for this view, if
-- any. If this view does not require any parameters, the set_parameters
-- function may be deleted.
-- This function should always return 1 and is called as follows
-- select col1, col2, ..., colN
-- from my_view
-- where 1 = my_view_vw.set_parameters(p1, p2, p3, ..., pN);
begin
g_var1 := pi_whatever1;
g_varN := pi_whateverN;
return 1;
end set_parameters;
function valid_parameters
return boolean
is
-- Customize...
-- Assumes that set_parameters has been called to set the value of the view
-- parameters.
l_valid boolean := true;
begin
return l_valid;
end valid_parameters;
procedure reset_parameters
is
-- Customize...
-- This is called at the end of the get_view function to reset the view
-- parameters for the next caller.
begin
g_var1 := null;
g_varN := null;
end reset_parameters;
function get_view
return table_type
pipelined
is
-- build and return each row for the view...
l_row row_type;
begin
if valid_parameters then
-- do your process to populate the l_row variable here...
pipe row (l_row);
end if;
reset_parameters;
exception
when others then
reset_parameters;
raise;
end get_view;
end demo_vw;
show error package body demo_vw
create or replace view demo
as
select * from table(demo_vw.get_view);