[oracle] How to return a resultset / cursor from a Oracle PL/SQL anonymous block that executes Dynamic SQL?

I have this table:

ALLITEMS
---------------
ItemId  | Areas
---------------
1       | EAST
2       | EAST
3       | SOUTH
4       | WEST

The DDL:

drop table allitems;

Create Table Allitems(ItemId Int,areas Varchar2(20));
Insert Into Allitems(Itemid,Areas) Values(1,'east');
Insert Into Allitems(ItemId,areas) Values(2,'east');
insert into allitems(ItemId,areas) values(3,'south');
insert into allitems(ItemId,areas) values(4,'east');

In MSSQL, to get a cursor from a dynamic SQL I can do:

DECLARE @v_sqlStatement VARCHAR(2000);
SET @v_Sqlstatement = 'SELECT * FROM ALLITEMS';
EXEC (@v_sqlStatement); --returns a resultset/cursor, just like calling SELECT 

In Oracle, I need to use a PL/SQL Block:

SET AUTOPRINT ON;
DECLARE
 V_Sqlstatement Varchar2(2000);
 outputData SYS_REFCURSOR;
BEGIN
 V_Sqlstatement := 'SELECT * FROM ALLITEMS';
 OPEN outputData for v_Sqlstatement; 
End;
--result is : anonymous block completed

**But all I get is

anonymous block completed".

How do I get it to return the cursor?

(I know that if I do AUTOPRINT, it will print out the information in the REFCURSOR (it's not printing in the code above, but thats another problem))

I will be calling this Dynamic SQL from code (ODBC,C++), and I need it to return a cursor. How?

This question is related to oracle plsql

The answer is


in SQL*Plus you could also use a REFCURSOR variable:

SQL> VARIABLE x REFCURSOR
SQL> DECLARE
  2   V_Sqlstatement Varchar2(2000);
  3  BEGIN
  4   V_Sqlstatement := 'SELECT * FROM DUAL';
  5   OPEN :x for v_Sqlstatement;
  6  End;
  7  /

ProcÚdure PL/SQL terminÚe avec succÞs.

SQL> print x;

D
-
X

This setting needs to be set:

SET SERVEROUTPUT ON 

You should be able to declare a cursor to be a bind variable (called parameters in other DBMS')

like Vincent wrote, you can do something like this:

begin
  open :yourCursor
    for 'SELECT "'|| :someField ||'" from yourTable where x = :y'
      using :someFilterValue;
end;

You'd have to bind 3 vars to that script. An input string for "someField", a value for "someFilterValue" and an cursor for "yourCursor" which has to be declared as output var.

Unfortunately, I have no idea how you'd do that from C++. (One could say fortunately for me, though. ;-) )

Depending on which access library you use, it might be a royal pain or straight forward.