User Guide

SAP AG November 2002

SAP DB OLAP

SAP DB OLAP is a database instance type [Page 132] of the SAP DB database system.

Online Analytical Processing (OLAP) technologies enable you to perform flexible analyses

from a variety of business perspectives. It is based on a multi-dimensional data model that is

achieved using relational database tables.

One application example is the Business Warehouse System. In contrast to SAP DB OLTP

[Page 149] systems, a Business Warehouse System is configured so that large quantities of

historical and operative data can be formatted with acceptable response times.

SAP DB OLTP

SAP DB OLTP is a database instance type [Page 132] of the SAP DB database system. SAP

DB is a relational database system that was developed for OLTP (Online Transaction

Processing). The database system is optimized to process individual transactions fast in

environments with a high number of users and large databases.

SAP DB User Classes

The SAP DB database system differentiates between two main user classes:

Database Manager Operator (DBM Operator) [Page

134]

•

• Database Users [Page

136]

Savepoint

The system carries out a backup action at regular intervals for the most important database

information. This backup action is known as a savepoint.

It writes all changed pages [Page

146] held in the data cache [Page 130] to the data area

[Page 131] .

The data cache contains, among other things, the undo log files [Page

48]. As these are

also permanently backed up to the data area by a savepoint, the database instance

[Page 132] can be restored to a transaction-consistent state in a restart [Page 146].

•

• At the time of a savepoint, the data of all open transactions [Page

152] is written to the

transaction file [Page 152].