Monday, March 3, 2008

Difference between ODS and DSO objects

Since SAP BW version 7.x there is a new term introduced for former ODS (Operational Data Store) object. DSO stands for Data Store Object. Some general information about ODS/DSO: In principle from data warehousing point of view such an objects are serving for storing of data from multiple sources to make analyses of data and simplifying reporting. Since data is coming from different sources data needs to be cleansed (e.g. redundancy) and consolidated (e.g. from business point of view). ODS/DSO objects store data in detailed level (atomic). In addition pure “data warehouse theory definition” would be that data to ODS/DSO is captured in “real time” or “near real time” mode and there is bigger portion of data available as opposite to data warehouse’s cubes. ODS/DSO is combining key field (e.g. business document or its item) with data field (e.g. business document status and other properties) as a key figures. There is nothing multidimensional (no dimension neither fact tables) with ODS/DSO as with cubes. Data in ODS/DSO is stored in transparent (flat) database tables. ODS/DSO objects are reportable.

In BW 3.x following types of ODS are used:

1. Standard ODS:

i. Inbound ODS object – or Inflow ODS where the data is stored in the same form as it is when delivered from the source system.

ii. Consistent ODS object - Data is stored here in granular form and consolidated.

iii. Application-related ODS object – data is combined according to the business process rules and serves as a basis for operative reporting.

2. Transactional ODS object – data is immediately available here for reporting no data is stored in different versions (active, delta, modified).

In BW 7.x following types of ODS were introduced:

1. Standard DSO object – as standard 3.x ODS; 3 tables with different data version (new/active/delta) data.

2. DSO object for direct update - as transactional 3.x ODS; data in a single version.

3. Write optimized DSO - contains only one table of active data; data is loaded using the data transfer process.

7.x DSO types differences:


2 comments:

Mamta "Tulip" said...

Very good explanation..thanks

Anonymous said...

good one