Matakuliah
Tahun
Versi
: M0184 / Pengolahan Data Distribusi
: 2005
:
Session – 6
DISTRIBUTED DATABASE
ARCHITECTURE
OBJECTIVES
• DISTRIBUTED DATABASE PRODUCTS AND
PROTOTYPE
• MULTIDATABASE SYSTEM
TWO PRODUCTS
• INGRES/STAR
• ADR/D-NET
INGRES/STAR
• Accessible from all the nodes in the network
without the user having to know where the data
actually resides
• Client Process paradigm
• Important fundamental component Global
Communication Architecture (GCA)
INGRES/STAR
INGRES/STAR, provides :
• A global query optimizer
• Vertical and horizontal fragmentation /
partitioning
• A global data dictionary
• Several relation DB Interfaces
• Heterogeneity of operating system and
machines through the gateway feature
ARD/D-NET
• ARD/D-NET software module manages the
entire DB environment, coordinating all activities
within the system, including interaction with the
user, filtering and routing data requests to the
extent that the system support this, handling
telecommunication link between nodes and
maintaining the status of the distributed directory
• The products is design to operate under a
variety of IBM operating systems
• System allows full portability between PCs and
mainframes called CA-DB/PC
ARD/D-NET
ARD/D-NET capabilities :
• Support for multiple databases at various
network nodes
• Processing of shared databases by many
machines
• Replication and partitioning data
• Location transparency and independence for
user and their programs
• Excellent security and authorization features,
and efficient scheduling of concurrent
transactions.
Two Multidatabase Systems
• MULTIBASE
• DISTRIBUTED QUERY SYSTEM
MULTIBASE
• Design by computer corporate of America, using
a simple functional Query language (DAPLEX)
• All operations which are necessary to access
data relevant to a query are provided
automatically and transparently to the user by
multibase
• The operation includes : locating the data
needed to service query, knowing the local
formats and the query language, breaking the
global query, resolving any inconsistency that
may occur between data, combining the partial
result, and presenting the result.
Distributed Query System (DQS)
• DQS that has been develop by CRAI for IBM
environments, is a retrieval only multidatabase
system using the relational data model for its
global data model and SQL as its query
language
• It work over IMS, IDMS, ADABAS and DB2 local
databases.
• DQS provides : transparency over languages,
data models and distribution, and pre-existing
DB are lft unaltered.