31. What is the significance of ODS in BIW?
An ODS Object serves to store consolidated and debugged transaction data on a document level (atomic level). It describes a consolidated dataset from one or more InfoSources. This dataset can be analyzed with a BEx Query or InfoSet Query. The data of an ODS Object can be updated with a delta update into InfoCubes and/or other ODS Objects in the same system or across systems. In contrast to multi-dimensional data storage with InfoCubes, the data in ODS Objects is stored in transparent, flat database tables.
32. What are the different types of source system?
SAP R/3 Source Systems, SAP BW, Flat Files and External Systems.
33. What is Extractor?
Extractor is a data retrieval mechanism in the SAP source system, which can fill the extract structure of a data source with the data from the SAP source system datasets. The extractor may be able to supply data to more fields than exist in the extract structure.
34. Explain open SQL vs native SQL?
ABAP Native SQL allows you to include database-specific SQL statements in an ABAP program. Most ABAP programs containing database-specific SQL statements do not run with different databases. If different databases are involved, use Open SQL. To execute ABAP Native SQL in an ABAP program, use the statement EXEC. Open SQL (Subset of standard SQL statements), allows you to access all database tables available in the R/3 System, regardless of the manufacturer. To avoid conflicts between database tables and to keep ABAP programs independent from the database system used, SAP has generated its own set of SQL statements known as Open SQL.
35. What are datasets?
The sequential files (processed on application server) are called datasets. They are used for file handling in SAP.
36. What are internal tables check table, value table, and transparent table?
Internal table: It is a standard data type object, which exists only during the runtime of the program. Check table: Check table will be at field level checking. Value table: Value table will be at domain level checking ex: scarr table is check table for carrid. Transparent table: - Exists with the same structure both in dictionary as well as in database exactly with the same data and fields.
37. What are the major benefits of reporting with BW over R/3? Would it be sufficient just to Web-enable R/3 Reports?
Performance — Heavy reporting along with regular OLTP transactions can produce a lot of load both on the R/3 and the database (cpu, memory, disks, etc). Just take a look at the load put on your system during a month end, quarter end, or year-end — now imagine that occurring even more frequently. Data analysis — BW uses a Data Warehouse and OLAP concepts for storing and analyzing data, where R/3 was designed for transaction processing. With a lot of work you can get the same analysis out of R/3 but most likely would be easier from a BW.
38. How can an ERP such as SAP help a business owner learn more about how business operates?
In order to use an ERP system, a business person must understand the business processes and how they work together from one functional area to the other. This knowledge gives the student a much deeper understanding of how a business operates. Using SAP as a tool to learn about ERP systems will require that the people understand the business processes and how they integrate.
39. What is the difference between OLAP and Data Mining?
OLAP - On line Analytical processing is a reporting tool configured to understand your database schema, composition facts and dimensions. By simple point-n-clicking, a user can run any number of canned or user-designed reports without having to know anything of SQL or the schema. Because of that prior configuration, the OLAP engine “builds” and executes the appropriate SQL. Mining is to build the application to specifically look at detailed analyses, often algorithmic; even more often misappropriate called “reporting.
40. What is Extended Star Schema and how did it emerge?
The Star Schema consists of the Dimension Tables and the Fact Table. The Master Data related tables are kept in separate tables, which has reference to the characteristics in the dimension table(s). These separate tables for master data are termed as the Extended Star Schema.
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