Wednesday 4 February 2015

SAP Business Objects Universe Designer Interview Questions (Part2)

11. What type of connections Designer provides?
DESIGNER provides three types of connections: (Tools ? Connections)
• Secured connection (Default): Stores the connection in the security domain of the BO repository to centralize and control access to sensitive or critical data. Designers and supervisors have the right to create this type of connection.
• Shared connection: Specifies that multiple users share the connection. All users who have access to this connection can use it and edit it. If you installed BO in Stand-Alone mode, the connection by default is stored in the sdac.lsi file (LocData subfolder). If you installed BO in Shared mode, the connection by default is stored in the sdac.ssi file (ShData subfolder). Designers and users have the right to create this type of connection.
• Personal connection: Specifies that the connection belong to the user who defined it. Other users cannot use or modify the connection. If you installed BO in Stand-Alone mode, the connection by default is stored in the pdac.lsi file (LocData subfolder). If you installed BusinessObjects in Shared mode, the connection by default is stored in the pdac.ssi file (ShData subfolder). Designers and users have the right to create this type of connection.

12. What are Universe parameters?
These parameters define the universe. They are Definition, Summary, Strategies, Controls, SQL and Links.
• Summary
Statistics of objects, joins, conditions, classes, contexts, hierarchies and alias in a universe. We get it from the Summary tab of the Universe parameters or File ? Parameters.
• Controls
The Control settings allow to limit the size of the result set and the execution time of queries.
• SQL
These parameter controls the query (allows use of subqueries, allows use of union, intersect and minus operators) and SQL generation options for the universe.
• Links
This links tab is used with dynamically linked universes.

13. What are Strategies?
A strategy is a script that automatically extracts structural information from a database or flat file. There are two types of strategies:
1. Built-in strategies
2. External strategies.

14. What is Build -in Strategy?
DESIGNER uses the following built-in strategies for creating the components of universes:
• The Objects Creation strategy, which tells DESIGNER how to define classes and objects automatically from the database’s tables and columns.
• The Joins Creation strategy, which tells DESIGNER how to define joins automatically from the database’s tables and columns.
• The Table Browser strategy, which tells DESIGNER how to read the table and column structures from the database’s data dictionary.

15. What is External strategy?
In the external strategy file you can customize an existing strategy or create your own.
External strategy files are named according to the following convention:
StxxxxEN.txt
where St means strategy, xxxx is an abbreviation for the RDBMS, and EN is the language in which Business Objects products are installed (EN =English)
For Oracle: Stora7en.txt in the Oracle folder

16. What is the list mode?
List mode command (View ? List Mode) provides list of all the tables, joins, and contexts.

17. What is a join?
A join is a relational operation that causes two or more tables with a common domain to be combined into a single table. The purpose of joins is to restrict the result set of a query run against multiple tables.
DESIGNER supports: • Equi-joins • Theta joins • Outer joins • Shortcut joins
Equi or Inner or Natural or Simple join: is based on the equality between the values in the column of one table and the values in the column of another. Because the same column is present in both tables, the join synchronizes the two tables.
? Self-Join: join a table to itself i.e create a self-join to find rows in a table that have values in common with other rows in the same table.
Theta or Non-Equi join: links tables based on a relationship other than equality between two columns.
Outer join: links two tables, one of which has rows that do not match those in the common column of the other table.
? Left Outer Join: All records from first table with matching rows from second.
? Right Outer Join: All records from second-named table with matching rows from left.
? Full outer join: All rows in all joined tables are included, whether they are matched or not.
Shortcut join: can be used in schemas containing redundant join paths leading to the same result, regardless of direction. Improves SQL performance.

18. What is Cardinality?
Cardinality expresses the minimum and maximum number of instances of an entity B that can be associated with an instance of an entity A. The minimum and the maximum number of instances can be equal to 0, 1, or N.
Cardinalities indicate whether the relationship or join between two tables is one-to-many (1,N), one-to-one (1,1), or many-to-many (N, N). Because a join is bi-directional, it must always have two cardinalities.

19. What is a Cartesian product?
A Cartesian product is the result of a query in which two or more tables are not linked by a join.
If executed, the report shows results for each possible combination of each table row.

20. Why do you perform 'Integrity Check’?
• It detects any errors in the objects, joins, conditions, and cardinalities of your universe.
• It detects whether there are any loops in the joins.
• It detects whether contexts are necessary.
• It determines whether any changes were made to the database to which the universe is connected.
More Questions & Answers :-
Part1  Part2  Part3  Part4  Part5 

No comments:

Post a Comment