Browse Prior Art Database

Technique for Fast Query of a LAN Based Database

IP.com Disclosure Number: IPCOM000107345D
Original Publication Date: 1992-Feb-01
Included in the Prior Art Database: 2005-Mar-21
Document File: 3 page(s) / 98K

Publishing Venue

IBM

Related People

Purdy, MG: AUTHOR [+2]

Abstract

A pair of processes (programs) is disclosed that supports a database existing on a Local Area Network (LAN) file server (or some type of distributed network) which can be updated by users while at the same time providing users with almost immediate access to the added or changed information as the database is updated, without sacrificing query response time.

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

Technique for Fast Query of a LAN Based Database

       A pair of processes (programs) is disclosed that supports
a database existing on a Local Area Network (LAN) file server (or
some type of distributed network) which can be updated by users while
at the same time providing users with almost immediate access to the
added or changed information as the database is updated, without
sacrificing query response time.

      The programs combine the fast retrieval capabilities of a local
single-user copy of a database with the advantages of access to a
common database containing shared information.

      The first program being described is called MASTER. MASTER is
the master copy of the database program and its associated database
file(s) which reside on the LAN file server.  There is only one
MASTER.  The second process (or program) is CLIENT.  CLIENT is a
client copy of the database program residing on another (non-server)
machine, but the same LAN domain as the server.  CLIENT is able to
communicate with MASTER via the LAN interprocess communications
mechanism (e.g., pipes).  Note that there can be many instances of
CLIENT, although this description will normally describe only one at
a time.

      The technique employed by the programs is as follows:
      1.   There is a registration process where CLIENT establishes a
"session" with MASTER.  A unique pathway or pipe is established
between MASTER and CLIENT so that CLIENT can be informed of future
updates to the database.  As part of the registration process, MASTER
provides a mechanism whereby CLIENT can get a copy of the current
level of the database, if necessary.
      2.   All instances of CLIENT communicate database update
requests to MASTER via a single pathway (pipe) monitored by MASTER.
Timestamps are kept in the database with the entities updated and are
included as part of update requests to guarantee that instances of
CLIENT requesting updates have received the latest...