Components of ETL
Services at Database of File Level
Operational Data Store: It stores detailed data and supports
tactical, day-to-day decision making. A SAP view ODS as a near real-time
informational environment that supports operational reporting by
interacting with existing transactional systems, data warehouses, or
analytical applications. SAP BW allows flexible access to data in the
ODS, the data warehouse, and the multidimensional models.
Data Marts: A data mart provides the data needed by a decentralized
function, department, or business area. You need to weight the pros and
cons before developing a data mart. For example, a data mart can be
implemented faster and cheaper than a data warehouse, sometimes costing
80% less than a full data warehouse. But as data marts proliferate, the
cost advantages can disappear. The IT organization must maintain the
individual data marts and the multitude of ETL and warehouse management
processes that go with them. Multiple data marts can complicate data
integration efforts, increase the amount of inconsistent data, require
more business rules, and create the data stovepipes that data
warehousing strives to eliminate.
Interfaces: The data mart interface enables users to transfer and
update transactional data and metadata from one SAP BW system to other
SAP BW systems.
Open Hub Services: The open hub service is used to share data in SAP
BW with non-SAP data marts, analytical applications, and other
applications. This service controls data distribution and maintains data
consistency across systems. With the open hub service, actual data and
the corresponding metadata are retrieved from InfoCubes or ODS objects.