|Oracle COM Automation Feature Developer's Guide
Release 9.0.1 for Windows NT
Part Number A90169-01
This chapter provides an overview of the Oracle COM Automation installation and post-installation configuration tasks.
This chapter contains these topics:
The Oracle COM Automation Feature package is included as part of your Oracle installation. It contains the features and demos that illustrate how to use this product to solve real-world problems.
The Oracle9i Database installation guide for Windows for installation instructions
The COM Automation package includes the following PL/SQL and Java components:
Oracle COM Automation PL/SQL feature
orawpcom.dll is located in the
All other components are located in the
Oracle COM Automation Java feature
orawcom.dll is located in the
\bin directory. All other components are located in the
Note the following system requirements.
For this release, Oracle has renamed
orawpcom.dll. If you are migrating from Oracle 8i, you must re-run
comwrap.sql to continue using Oracle COM Automation Feature for PL/SQL.
"Configuring Oracle COM Automation Feature for PL/SQL" for information on re-running
Configuration procedures differ for PL/SQL and for Java.
CREATE LIBRARYprivilege to the database users that will use Oracle COM Automation Feature. For example:
comwrap.sqlscript at the SQL*Plus prompt:
ORACLE_BASE\ORACLE_HOME represents the Oracle home directory where Oracle COM Automation Feature is installed.
You will receive several "ORA-04043: object XXXX does not exist" messages when you run this script for the first time. These messages are normal.
loadjavaon the command line as follows:
hr is the user that uses Oracle COM Automation Feature.
Oracle9i Java Developer's Guide for further information on the
When using Oracle COM Automation Feature for PL/SQL, there are specific requirements for the
tnsnames.ora files that are described in this section.
For Oracle COM Automation Feature for Java, no special modifications to these files are required.
Because Oracle COM Automation Feature for PL/SQL relies on external procedure callouts, you must configure the listener and Oracle Net remote procedure call (RPC) mechanism for the feature to work.
The following are examples of
tnsnames.ora files that can be used with inter-process communication (IPC) to invoke external stored procedures.
Oracle9i Net Services Administrator's Guide for additional information on configuring the
STARTUP_WAIT_TIME_LISTENER = 0
CONNECT_TIMEOUT_LISTENER = 10
TRACE_LEVEL_LISTENER = off
(SID_NAME = ORCL)
(SID_NAME = plsextproc)
PASSWORDS_LISTENER = (oracle)
An "ORA-28575: unable to open RPC connection to external procedure agent" error message indicates one of two possible listener problems.
Problem: The listener is not started.
Action: You must start the
Listener service from the Control Panel or the command prompt.
The Control Panel window appears.
The Services dialog box appears.
Listenerin the list and verify that it has a status of Started. If it does not, select it and click Start.
Enter the following command to start an Oracle service at the command prompt:
where service is a specific service name, such as
Problem: The listener is not configured correctly.
Action: You must modify the
"Configuring the Listener for PL/SQL" for information on how to configure these files
Oracle COM Automation feature supports the use of Distributed Component Object Model (DCOM) to access remote COM objects over a network.
In order to authenticate the client's access to the remote computer, DCOM passes the appropriate security credentials to the remote computer. The remote computer validates the security credentials and allows DCOM to proceed.
These security credentials are based on the domain user's privileges associated with either the client's listener service or database service. Table 2-1, "Services That Determine Security Credentials" indicates the determining service for COM Automation for PL/SQL and Java.
|COM Automation Feature for...||Is Determined by This Service|
Oracle database service
In order to use DCOM, you must configure security settings on the following:
The configuration for the computer running the database instance requires setting the listener and the database service to the same domain user.
The procedure for setting a service to a domain user is described below, where the service to be set is selected in step 3.
You must follow this procedure twice, once to set the listener and once to set the database service. The order is unimportant.
Listeneror the database service.
Configuring the computer containing the remote object requires using the
dcomcnfg.exe tool provided by Microsoft to configure the computer's DCOM security settings.
This tool enables you to set the access permissions, launch permissions, and configuration permissions for a specific COM object or all COM objects on a computer.
dcomcnfg.exe tool, set the following:
If the COM object attempts to perform an action for which it does not have permission, DCOM denies the operation and returns a security violation to Oracle COM Automation Feature. It is essential that you configure the DCOM security properly and provide the Oracle database with the necessary permissions.