Kbase 8774: How to troubleshoot RDB Gateway problems
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
10/05/1998 |
|
How to troubleshoot RDB Gateway problems
910801-ctp01
INTRODUCTION:
=============
This Progress Software Technical Support Knowledgebase Entry
details the information you need to resolve VMS Rdb Gateway
questions and problems.
WHY YOU NEED TO DO THIS:
========================
Understand the VMS Rdb Gateway and how it works.
The Gateway is a software module that lets you write
PROGRESS applications that run against non-PROGRESS
databases.
PROCEDURAL APPROACH:
====================
Please read the following information and answer as many of
questions 3 to 11 as you can to help determine the source of
the problem and gain the information necessary to resolve it.
1. How do I use the Rdb database gateway?
To use the Rdb database gateway, copy the structure of
the database, or the file definitions (the database
schema), that you want to access and place the copy
in a PROGRESS database. Then PROGRESS can compile
and run its management 4GL procedures that access
the target database.
The schema copy made during the schema copying process
is called a gateway schema. The copy of an Rdb data
definition is called the Rdb gateway schema. The PROGRESS
database that contains the gateway schema is known as the
schema holder.
Create a schema holder and copy the Rdb data definitions
into the schema holder. This combination is the whole
database gateway.
2. How does the Rdb Gateway access data?
When you execute a PROGRESS application that accesses
an Rdb database, the gateway translates the 4GL procedures
into Binary Language Representation, (BLR) requests.
BLR is Digital's protocol to communicate with Rdb.
Rdb compiles the BLR request and returns a handle.
PROGRESS attaches a message to the handle and makes
the request. Rdb fills the request and sends back
a message. PROGRESS translates the data into readable
form and displays it.
3. What PROGRESS Version is being used?
The Rdb Gateway is available beginning with PROGRESS
Version 6.2B. To verify the version you have, enter
the PROGRESS editor and the banner will display
the version number.
Or type out the DLC:version file.
4. Are the Rdb files correctly installed?
Verify that the Rdb files were loaded successfully.
They are located in the [DLCRDB] and [DLCGATE] directories.
The files must include:
DEMORDB.BI, DEMORDB.DB, DEMORDB.LG,
EMPTY.DB, PROGRES.EXE,
RDBDEMO.RDB, RDBDEMO.SNP, _MPROSRV.EXE
5. Have the PROGRESS logicals been defined?
Specifically: PROEXE must be set to the correct version
of the PROGRESS executable.
PROCFG must be set to the correct PROGRESS configuration
file for the version you are running.
6. Was PROBUILD executed?
A new PROGRES.EXE is created when you run PROBUILD.
The PROEXE logical must be reset to this new image.
7. Is the Rdb monitor running?
The monitor is responsible for maintaining a log of
database activity. It extends the Rdb database files
when required. When changes are made to an Rdb database
the monitor will be notified. PROGRESS does not require
the Rdb monitor, the Rdb database does.
8. Are the databases connected?
Use the CONNECTED Function for each database to determine
if they are connected. The Rdb database must be connected
in order to access the data within it. To do so:
o Connect to the schema holder that holds the
Rdb gateway schema for the target Rdb database.
o Connect to the Rdb database.
Connect to databases by using the following methods:
o Use startup parameters at the command line.
o Use the CONNECT statement from a PROGRESS
procedure or session.
o Use the auto-connect feature from within POGRESS.
o Use the PROGRESS Data Dictionary from within
PROGRESS.
9. Can the problem be duplicated against the
DemoRdb database supplied with the product?
In order to determine if a bug exists, we need
to be able to duplicate the problem at will.
When the problem is duplicated at will against
the demo database PROGRESS provides, it can
then be addressed by PROGRESS development.
10. What errors are being generated?
Use the Messages option in PROGRESS Help to
further understand the errors being generated.
11. What is the VMS version and the Rdb version
you are currently running?
You need Rdb version 3.01 or higher and VMS
version 5.3 or higher to run the gateway.
12. Read the documentation and walk through
the Rdb Gateway tutorial. It will provide
an invaluable resource in understanding the
Gateway and how it works.
REFERENCES TO WRITTEN DOCUMENTATION:
====================================
Database Gateways Guide - Chapter 1
Introduction to Database Gateways
Database Gateways Guide - Chapter 4
The Rdb/VMS Database Gateway
Database Gateways Guide - Appendix A
The Remote Database Gateway Environment
Version 6 Gateway Documentation Bulletin
VMS - Rdb Manual
Progress Software Technical Support Note # 8774