Input/Output Parameters and Result Sets
Input and output parameters can be passed to stored procedures. The DB Interface Module uses RWDBColumn to describe a parameter to a stored procedure.
The RWDBStoredProc::fetchReturnParams() must be used to load the output parameters.
There is no limit on the number of input and output parameters that can be exchanged between an RWDBStoredProc and a PL/SQL procedure.
The DB Interface Module provides support for stored procedures that contain cursor variables. A cursor variable is a reference to a cursor that is defined and opened on an Oracle server. In the following sample stored procedure, written in PL/SQL, myCursor is a cursor variable.
 
create package myProcPkg as
type cursvar is ref cursor return employees%ROWTYPE;
end myProcPkg;
 
create procedure myProc(myDept in number,
myCursor in out myProcPkg.cursvar,
mySalary in number) as
begin
open myCursor for select * from employees where DEPTNO =
myDept and SALARY <= mySalary;
end myProc;
The DB Interface Module enables your application to receive an RWDBResult containing the result sets returned by the reference cursors from the execution of a stored procedure. Notice in the following code fragment that the user does not explicitly shift a cursor parameter into the procedure:
 
RWDBStoredProc myStoredProc = aDatabase.storedProc("myProc");
int myDept = 30, int mySalary = 50000;
myStoredProc["myDept"] << myDept;
myStoredProc["mySalary"] << mySalary;
RWDBResult result = myStoredProc.execute();