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Siebel Data Warehouse Database Requirements

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The Siebel Data Warehouse is a database that contains the star schemas created by Informatica.

Although it is technically possible to put the Siebel Data Warehouse in the same database as the Siebel transactional database, it is not recommended for performance reasons. The Siebel transactional database is structured as an online transaction processing (OLTP) database, whereas the Siebel Data Warehouse is structured as an online analytical processing database. Each is optimized for its own purpose. The reasons for not combining the two databases are:

• The analytical queries interfere with normal use of the transactional database, which is entering and managing individual transactions.
• The data in a transactional database is normalized for update efficiency. Analytical queries join several normalized queries and will be slow (as opposed to prejoined, denormalized analytical tables).
• Historical data cannot be purged from a transactional database, even if not required for current transaction processing, because you need it for analysis. (By contrast, the analytical database is the warehouse for historical as well as current data.) This causes the transactional database to further slow down.
• Transactional databases are tuned for one specific application, and it is not productive to use these separate transactional databases for analytical queries that usually span more than one functional application.
• The analytical database can be specifically tuned for the analytical queries and Extract-Transform-Load (ETL) processing. These are quite different from transactional database requirements.
• The Siebel Data Warehouse repository stores all of the Informatica object definitions for the ETL mappings that populate the Siebel Data Warehouse. It is a series of repository tables that are stored in a database, which can be the transactional, analytical, or a separate database.

The Siebel Data Warehouse works with database management systems (DBMS). In addition to the general requirements, there are additional DBMS-specific requirements depending on the DBMS you are using.

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