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Extendable Control Block Structure Interface Between SQL Database Servers and their Clients

IP.com Disclosure Number: IPCOM000107867D
Original Publication Date: 1992-Mar-01
Included in the Prior Art Database: 2005-Mar-22
Document File: 3 page(s) / 114K

Publishing Venue

IBM

Related People

Devany, EP: AUTHOR [+5]

Abstract

This article describes an efficient method for passing the necessary parameters and data between OS/2* Database Manager Clients and OS/2 Database Manager Servers. It is designed to support program calls, remote procedure calls, or distributed database protocols such as the IBM Distributed Relational Database Architecture (DRDA). (Image Omitted)

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Extendable Control Block Structure Interface Between SQL Database Servers and their Clients

       This article describes an efficient method for passing
the necessary parameters and data between OS/2* Database Manager
Clients and OS/2 Database Manager Servers.  It is designed to support
program calls, remote procedure calls, or distributed database
protocols such as the IBM Distributed Relational Database
Architecture (DRDA).

                            (Image Omitted)

      The SQLRA is the current control block structure that is used
as an interface to the OS/2 DBM.  It was designed as a private
interface to be used via a program call in the same process.  The
caller and the callee operate totally in the same operating system
environment and even in the same process.  The SQLRA contains the
information that the database server requires in order to process a
request.  It contains a type field that describes the request type
(Open Cursor, Fetch, etc.).  It embeds some parameters within it
(such as the program name) and indirectly addresses other parameters
(such as the SQLDA).  Some fields have double meaning (output SQLDA
pointer used as statement number in a compile request).

      The OS/2 Database Manager Server is currently making the
following design changes:
     1.  The client process is separate from the server process.
This means changing the current program call to a task and memory
switch. This requires that the addresses in the SQLRA be updated to
point to the new memory areas for the indirect references.
      2.  A standardized Remote Procedure Call will be used by the
OS/2 DBM between its clients and its servers.  The clients and the
servers could be in different operating systems and in different code
pages which means that data transformations must be performed at the
interface.
      3.  The client/server interface is being "opened". This means
that it is being published which will allow OEM clients to access the
OS/2 DBM Server and for OEM servers to service the OS/2 DBM clients.

      These changes make the current SQLRA obsolete.  Its structure
requires that the code making the process change understand all the
request types.  The code supporting the RPC must know the data type
for all of the parameters of all the request types for data
transformations. Also double meaning for fields within the SQLRA is
too 'private' for external publications.

      A new structure (SQLJRA) solves the problems c...