The following Knowledge Base article gives an in-depth
example, using RDO, of all the possible ways to return a Recordset back from a
stored procedure. The example in this article is a simplified version:
174679 How To Retrieve Resultsets from Oracle Stored Procedures
NOTE: The Recordsets created by the Microsoft ODBC Driver for Oracle ,
using Oracle stored procedures, are Read Only and Static. Retrieving a
Recordset requires you to create an Oracle Package.
You can create
the sample project in this article in Visual Basic 5.0 or 6.0 and use ADO to
access and manipulate the Recordsets created by the Microsoft ODBC Driver for
Oracle version. You must have this driver to use the
recordsets-from-stored-procedures functionality discussed in this Knowledge
Base article:
174679 How To Retrieve Resultsets from Oracle Stored Procedures
(Currently, it is the only driver on the market
that can return a Recordset from a stored procedure.) If you want additional
information about using Visual Basic with Oracle, please see the following
Knowledge Base article, which uses RDO 2.0 in its examples:
167225 How To Access an Oracle Database Using RDO
NOTE: You must acquire and install the MDAC 2.1 or later stack for the
sample in this article. The following Microsoft Knowledge Base article explains
how to get the Oracle and MDAC components:
175018 How To Acquire and Install the Microsoft Oracle ODBC Driver
MDAC 1.5 contains ADO 1.5 and the Microsoft ODBC
Driver for Oracle version 2.0.
The MDAC 2.
x stack, which includes the 2.573 driver, can be downloaded from
the following Web address:
This article is broken up into two parts. The first part is a
step-by-step procedure for creating the project. The second part is a detailed
discussion about the interesting parts of the project.
Step-by-Step Example
- Run the following DDL script on your Oracle server:
DROP TABLE person;
CREATE TABLE person
(ssn NUMBER(9) PRIMARY KEY,
fname VARCHAR2(15),
lname VARCHAR2(20));
INSERT INTO person VALUES(555662222,'Sam','Goodwin');
INSERT INTO person VALUES(555882222,'Kent','Clark');
INSERT INTO person VALUES(666223333,'Jane','Doe');
COMMIT;
/
- Create the following package on your Oracle server:
CREATE OR REPLACE PACKAGE packperson
AS
TYPE tssn is TABLE of NUMBER(10)
INDEX BY BINARY_INTEGER;
TYPE tfname is TABLE of VARCHAR2(15)
INDEX BY BINARY_INTEGER;
TYPE tlname is TABLE of VARCHAR2(20)
INDEX BY BINARY_INTEGER;
PROCEDURE allperson
(ssn OUT tssn,
fname OUT tfname,
lname OUT tlname);
PROCEDURE oneperson
(onessn IN NUMBER,
ssn OUT tssn,
fname OUT tfname,
lname OUT tlname);
END packperson;
/
- Create the following package body on your Oracle server:
CREATE OR REPLACE PACKAGE BODY packperson
AS
PROCEDURE allperson
(ssn OUT tssn,
fname OUT tfname,
lname OUT tlname)
IS
CURSOR person_cur IS
SELECT ssn, fname, lname
FROM person;
percount NUMBER DEFAULT 1;
BEGIN
FOR singleperson IN person_cur
LOOP
ssn(percount) := singleperson.ssn;
fname(percount) := singleperson.fname;
lname(percount) := singleperson.lname;
percount := percount + 1;
END LOOP;
END;
PROCEDURE oneperson
(onessn IN NUMBER,
ssn OUT tssn,
fname OUT tfname,
lname OUT tlname)
IS
CURSOR person_cur IS
SELECT ssn, fname, lname
FROM person
WHERE ssn = onessn;
percount NUMBER DEFAULT 1;
BEGIN
FOR singleperson IN person_cur
LOOP
ssn(percount) := singleperson.ssn;
fname(percount) := singleperson.fname;
lname(percount) := singleperson.lname;
percount := percount + 1;
END LOOP;
END;
END;
/
- Open a new project in Visual Basic 5.0 or 6.0 Enterprise
edition. Form1 is created by default.
- Place the following controls on the form:
Control Name Text/Caption
-----------------------------------------
Button cmdGetEveryone Get Everyone
Button cmdGetOne Get One
- From the Tools menu, select the Options item. Click the
"Default Full Module View" option and then click OK. This will allow you to
view all of the code for this project.
- Paste the following code into your code window:
Option Explicit
Dim Cn As ADODB.Connection
Dim CPw1 As ADODB.Command
Dim CPw2 As ADODB.Command
Dim Rs As ADODB.Recordset
Dim Conn As String
Dim QSQL As String
Dim inputssn As Long
Private Sub cmdGetEveryone_Click()
Set Rs.Source = CPw1
Rs.Open
While Not Rs.EOF
MsgBox "Person data: " & Rs(0) & ", " & Rs(1) & ", " & Rs(2)
Rs.MoveNext
Wend
Rs.Close
End Sub
Private Sub cmdGetOne_Click()
Set Rs.Source = CPw2
inputssn = InputBox("Enter the SSN you wish to retrieve:")
CPw2(0) = inputssn
Rs.Open
MsgBox "Person data: " & Rs(0) & ", " & Rs(1) & ", " & Rs(2)
Rs.Close
End Sub
Private Sub Form_Load()
'Replace <User ID>, <Password>, and <Server> with the
'appropriate parameters.
Conn = "UID=*****;PWD=*****;driver=" _
& "{Microsoft ODBC for Oracle};SERVER=dseOracle;"
Set Cn = New ADODB.Connection
With Cn
.ConnectionString = Conn
.CursorLocation = adUseClient
.Open
End With
QSQL = "{call packperson.allperson({resultset 9, ssn, fname, " _
& "lname})}"
Set CPw1 = New ADODB.Command
With CPw1
Set .ActiveConnection = Cn
.CommandText = QSQL
.CommandType = adCmdText
End With
QSQL = "{call packperson.oneperson(?,{resultset 2, ssn, fname, " _
& "lname})}"
Set CPw2 = New ADODB.Command
With CPw2
Set .ActiveConnection = Cn
.CommandText = QSQL
.CommandType = adCmdText
.Parameters.Append .CreateParameter(, adInteger, adParamInput)
End With
Set Rs = New ADODB.Recordset
With Rs
.CursorType = adOpenStatic
.LockType = adLockReadOnly
End With
End Sub
Private Sub Form_Unload(Cancel As Integer)
Cn.Close
Set Cn = Nothing
Set CPw1 = Nothing
Set CPw2 = Nothing
Set Rs = Nothing
End Sub
- Go to the Project menu item and select References. Select
the "Microsoft Active Data Objects 2.x Library."
- Run the project. When you click on the "Get Everyone"
button, it executes this query:
QSQL = "{call packperson.allperson({resultset 9, ssn, fname, "_
& "lname})}"
This query is executing the stored procedure "allperson," which
is in the package "packperson" (referenced as "packperson.allperson"). There
are no input parameters and the procedure is returning three arrays (ssn,
fname, and lname) each with nine or fewer records. As stated in the following
Knowledge Base article:
174679 How To Retrieve Resultsets from Oracle Stored Procedures
you must specify the maximum number of rows you
will be returning. Please refer to the Microsoft ODBC Driver for Oracle Help
File and Knowledge Base article Q174679 for more information on this issue.
When you click on the "Get One," button it brings up an input box
that prompts you for an SSN. Once you input a valid SSN and click OK, this
query is executed:
QSQL = "{call packperson.oneperson(?,{resultset 2, ssn, fname, "_
& "lname})}"
The stored procedure, packperson.oneperson, uses a single input
parameter as the selection criteria for the Recordset it creates. Just like
packperson.allperson, the Recordset is constructed using the table types
defined in packperson. (See Knowledge Base article Q174679 for more
information.)
NOTE: You can only define input parameters for Oracle stored
procedures that return a Recordset. You cannot define output parameters for
these stored procedures.
These two stored procedures cover the basic
uses of stored procedures that return Recordsets. The first one will give you a
predefined set of records (i.e. everyone) and the second one will give you a
set of records (or just one record) based on one or more input parameters. Once
you have these recordsets, you can do inserts, updates, and deletes either
through stored procedures or SQL that you create on the client.