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If I understand the question, I believe you are asking what is horizontal and
vertical partitioning.
Horizontal partitioning is the ability to partition relations horizontally
across a distributed database. For example, a particular relation contains all
of a corporate banks customers. This bank has sites in Colorado Springs and
Dallas. Therefore, to horizontally partition the customers relation is to say
that records for customers in Colorado Springs will be stored locally in the
Colorado Springs Site, while records for customers in Dallas will be stored
locally in Dallas. However, all of the records make up the Distributed
Database (ie. Colorado Springs can still access Dallas acounts because this
partitioning is invisible to the user).
Vertical partitioning is the same concept, except that we are now splitting the
relation up vertically among multiple sites.
As for what ORACLE has I do not know. I do know that INGRES is talking about
implementing this to some degree in the future.
Hope this helps...
Craig
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"By vertical distribution we mean that there is a hierarchy of
processors. The transaction may enter and leave the computer system
at the lowest level. The lowest level may be able to process the
transaction or may execute certain functions and pass it up to the
next level. Some or all transactions eventually reach the highest
level, which will probably have access to online files or a data
base.
-----------
| | LEVEL 3 PROCESSOR
-----------
| |
| |
------- --------
| | | | LEVEL 2 PROCESSORS
-------- --------
| | | |
| | | |
--- --- --- ---
| | | | | | | | LEVEL 1 PROCESSORS
--- --- --- ---
[VERTICAL DISTRIBUTION DIAGRAM, 3 LEVELS OF PROCESSORS]
"The machine at the top of a hierarchy might be a computer system
in its own right, performing its own type of processing on its own
transactions. However, the data it uses are passed to it from the
lower-level systems. The machine at the top might be a head-office
system which receives data from factory, branch, warehouse, and
other systems.
By horizontal distribution we imply that the distributed processors
do not differ in rank. They are of equal status- peers- and we
refer to peer-coupled systems. A transaction may use only one
processor, although there are multiple processors available. On
some peer-coupled systems a transaction may pass from one system
to another, causing different files to be updated.
"[The next figure] illustrates horizontal distribution...."
----- ----- ------ ------
| | | | | | | | PROCESSORS
----- ----- ------ ------
| | | |
------------------------------------------ BUS
[Note: A wide area network is also illustrated in the original text]
Excerpted from "Design and Strategy for Distributed Data Processing"
by James Martin, Prentice-Hall 1981
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