how we improve the performance of report and universe?
- 4 Answers
- 13786 Views
- Accenture, IBM, I also Faced
- E-Mail Answers
Answer Posted / vamshi
optimization at universe level –
-> Modify Array Fetch parameter
-> Allocate weight to each table
-> Use shortcut joins
-> Use aggreagte functions
-> Use aggregate tables
-> Minimize usage of the derived tables
Modify Array Fetch parameter: The Array fetch parameter sets the maximum number of rows that are permitted in a FETCH proedure. For example, of the Array Fetch size is 20, and total rows are 100, then five fetches will be executed to retrieve the data, which will consume more time in comparison with one fetch.
Resolution: If network allows sending large arrays, then set Array fetch parameter to new larger value. This speed up the FETCH procedure, and reduce query processing time.
Allocating table weights: Table weight is a measure of how many rows there are in a table. Lighter tables have less rows than heavier tables. By default BusinessObjects sorts the tables from the lighter to the heavier tables. The order in which tables are sorted at the database level depends on your database. For example, Sybase uses the same order as BusinessObjects, but Oracle uses the opposite order. The SQL will be optimized for most databases, but not for Oracle where the smallest table is put first in the sort order. So, if you are using an Oracle database, you can optimize the SQL by reversing the order that BusinessObjects sorts the tables. To do this you must change a parameter in the relevant PRM file of the database.
Resolution: Business Objects settings, the ORACLE PRM file must be modified as below:
• Browse to directory Business Objects\BusinessObjects Enterprise
6\dataAccess\RDBMS\connectionServer\oracle.
• Open ORACLE.PRM file, change the REVERSE_TABLE_WEIGHT
value to N from Y.
Using Shortcut joins: Numbers of tables in join are more, even when selected objects are less. Even when no object of related table is selected, then also that table is appearing in the join condition. For e.g., If A_id object from A table of C table is selected with B table in between, then BO generated SQL shows that intermediate table ‘B’ table was present in ‘From’ clause.
Resolution: Shortcut joins allow users to skip intermediate tables and allow alternative paths between tables. Use of shortcut join reduces the number of tables used in query to improve SQL performance. Results in query performance improving from 1.5 minute to 30 seconds!!
Use aggregate functions: Data is aggregated on the subject of analysis (user selected criteria) at report level. This takes more processing time, as data from database is loaded in temporary
memory and then aggregated or processed to display.
Resolution: Use aggregate functions (e.g., sum, count, min, max) in measure objects at universe
level. Aggregate functions will aggregate the data at database level rather than at report level which will save on processing time at report level and also reduce the number of rows returned back to report.
Creating and using aggregate tables: Aggregate data are obtained by scanning and summarizing all of the records in the fact table at real-time which consumes more time.
Resolution: Aggregate tables contain pre-calculated aggregated data. Using aggregate tables
instead of detail tables enhances the performance of SQL transactions and speeds up query execution. Aggregate_Awareness function has ability to dynamically re-write SQL to the level of granularity needed to answer a business question. Aggregate tables allow for faster querying speed and increases query performance manifolds!!
Minimize usage of derived tables: Since derived tables are evaluated and executed at runtime, SQL tuning is not possible.
Resolution: Minimize the usage of derived tabled and replace them with tables or materialized
view. SQL tuning techniques such as creating index can be applied on tables or materialized views which will improve performance of BO reports
| Is This Answer Correct ? | 8 Yes | 0 No |
Post New Answer View All Answers
how many reports have u created ? explain a few.
can some body explain how migrate the BoXI r2 to BO 3.x and crystal reports XI r1 to Crystal report 2008 ?
Let me know the things we can do in webi and cannot do it in full client and vice verse for bo6.5?
What is report template in b.o?
Explain are data mart and data warehouse normalized or denormalized? Do both of them exist in?
Are data mart and dwh normalized or denormalized? Do both of them exist in the same tier?
What's the Functional & Architectural Differences between Business Objects & Web Intelligence Reports?
How to generate the report from excel sheet?
Explain and tell me about a situation where your analysis of a problem was deemed to be incorrect? What would you have done differently?
Explain is there any other repository domains rather than universe, security, document?
explain in detail about type 3?
What is Indexing? how did u implement indexing?
Explain what three things do you consider to be the most important factors for a manager?
How were the reports scheduled and how to resolve unexecuted documents?
Explain as a ba (business analyst) approaching a new piece of work, who would you interview and what questions would you ask?
