What is the difference between an ODS and a W/H?

Question Posted / g ruban

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What is the difference between an ODS and a W/H?..

Answer / tanmay kumar meher

An ODS is an environment that pulls together, validates,
cleanses and integrates data from disparate source
application systems. Thisbecomes the foundation for
providing the end-user community with an integrated view of
enterprise data to enable users anywhere in the
organisation to access information for strategic and/or
tactical decision support, day-to-day operations and
management reporting.

The defination of Data Warehouse is as follows.
? Subject-oriented, meaning that the data in the
database is organized so that all the data elements
relating to the same real-world event or object are linked
together;
? Time-variant, meaning that the changes to the data
in the database are tracked and recorded so that reports
can be produced showing changes over time;
? Non-volatile, meaning that data in the database is
never over-written or deleted, but retained for future
reporting;
? Integrated, meaning that the database contains data
from most or all of an organization's operational
applications, and that this data is made consistent.

Difference
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Ods
--------
Transactions similar to those of an
Online Transaction Processing System
Data Warehouse
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Queries process larger volumes of data
Ods
--------
Contains current and near current data
Data Warehouse
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Contains historical data
Ods
-----------
Typically detailed data only, often
resulting in very large data volumes
Data Warehouse
--------------
Contains summarised and detailed data,
generally smaller in size than on ODS

Ods
--------
Real-time and near real-time data loads
Data Warehouse
------------
Typically batch data loads

Ods
--------
Generally modeled to support rapid data
update
Data Warehouse
-----------------
Generally dimensionally modeled and
tunes to optimise query performance
Ods
------
Updated at the data field leve
Data Warehouse
---------------
Data is appended, not updated
Ods
-------
Used for detailed decision making and
operational reporting
Data Warehouse
----------------
Used for ling-term decision making and
management reporting

Ods
-----
Knowledge workers (customer service
representatives, line managers)
Data Warehouse
-------------
Strategic audience (executives, business
unit management)