11.How do perform real time data acquisition in BW system?
Ans: Real time data acquisition is based on moving data to Business Warehouse in real time. Data is sent to delta queue or PSA table in real time.
Real time data acquisition can be achieved in two scenarios −
By using InfoPackage for real time data acquisition using Service API.
Using Web Service to load data to Persistent Storage Area PSA and then by using real time DTP to move the data to DSO.
Real time Data Acquisition Background Process −
To process data to InfoPackage and data transfer process DTP at regular intervals, you can use a background process known as Daemon.
Daemon process gets all the information from InfoPackage and DTP that which data is to be transferred and which PSA and Data sore objects to be loaded with data.
12.What is InfoObject catalog?
Ans: InfoObjects are created in Info Object catalog. It is possible that an Info Object can be assigned to different Info Catalog.
13.What is the use DSO in BW system? What kind of data is stored in DSO’sWhat are the different components in DSO architecture?
Ans: To access data for reporting and analysis immediately after it is loaded,
14.What all data sources you have used to acquire data in SAP BW system?
- SAP systems (SAP Applications/SAP ECC)
- Relational Database (Oracle, SQL Server, etc.)
- Flat File (Excel, Notepad)
- Multidimensional Source systems (Universe using UDI connector)
- Web Services that transfer data to BI by means of push
15.When you are using SAP BI7.x, you can load the data to which component?
Ans: In BW 3.5, you can load data in Persistence Staging Area and also in targets from source system but If you are using SAP BI 7.0 data load should be restricted to PSA only for latest versions.
16.What is an InfoPackage?
Ans: An InfoPackage is used to specify how and when to load data to BI system from different data sources. An InfoPackage contains all the information how data is loaded from source system to a data source or PSA. InfoPackage consists of condition for requesting data from a source system.
Note that using an InfoPackage in BW 3.5, you can load data in Persistence Staging Area and also in targets from source system but If you are using SAP BI 7.0 data load should be restricted to PSA only for latest versions.
17.What is extended Star schema? Which of the tables are inside and outside cube in an extended star schema?
Ans: In Extended Star schema, Fact tables are connected to Dimension tables and dimension table is connected to SID table and SID table is connected to master data tables. In Extended star schema you have Fact and Dimension tables are inside the cube however SID tables are outside cube. When you load the transactional data into Info cube, Dim Id’s are generated based on SID’s and these Dim id’s are used in fact tables.
18.How extended Star schema is different from Star schema?
Ans: In Extended Star schema one fact table can connect to 16 dimensions tables and each dimension table is assigned with 248 maximum SID tables. SID tables are also called Characteristics and each characteristic can have master data tables like ATTR, Text, etc.
In Star Schema, Each Dimension is joined to one single Fact table. Each Dimension is represented by only one dimension and is not further normalized.
Dimension Table contains set of attribute that are used to analyze the data.
19.which Data store object is used?
Ans: DataStore object for direct update allows you to access data for reporting and analysis immediately after it is loaded. It is different from standard DSO’s in the way how it processed the data. Data is stored in same format in which it was loaded to DataStore object for direct update by the application.
20.Explain the structure of direct update DSO’s?
Ans: one table for active data and no change log area exists. Data is retrieved from external systems using API’s.
Below API’s exists −
- RSDRI_ODSO_INSERT: These are used to insert new data.
- RSDRI_ODSO_INSERT_RFC: Similar to RSDRI_ODSO_INSERT and can be called up remotely.
- RSDRI_ODSO_MODIFY: This is used to insert data having new keys.For data with keys already in the system, the data is changed.
- RSDRI_ODSO_MODIFY_RFC: Similar to RSDRI_ODSO_MODIFY and can be called up remotely.
- RSDRI_ODSO_UPDATE: This API is used to update existing data.
- RSDRI_ODSO_UPDATE_RFC: This is similar to RSDRI_ODSO_UPDATE and can be called up remotely.
- RSDRI_ODSO_DELETE_RFC: This API is used to delete the data.