Important Informatica interview questions and answers asked in Cognizant, Accenture, Deloitte, Google…
Informatica interview questions and answers
| 1. Can you use the mapping parameters or variables created in one mapping into another mapping? Answer: NO. We can use mapping parameters or variables in any transformation of the same mapping or mapplet in which U have created mapping parameters or variables. |
| 2. Can u use the mapping parameters or variables created in one mapping into any other reusable transformation? Answer: Yes. Because reusable transformation is not contained with any mapplet or mapping. |
| 3. How can you improve session performance in aggregator transformation? Answer: Use sorted input. |
| 4. What is aggregate cache in aggregator transformation ? Answer: The aggregator stores data in the aggregate cache until it completes aggregate calculations. When u run a session that uses an aggregator transformation, the Informatica server creates index and data caches in memory to process the transformation. If the Informatica server requires more space, it stores overflow values in cache files. |
| 5.What are the difference between joiner transformation and source qualifier transformation? Answer: You can join heterogeneous data sources in joiner transformation which we can not achieve in source qualifier transformation. U need matching keys to join two relational sources in source qualifier transformation. Where as u doesn’t need matching keys to join two sources. Two relational sources should come from same data source in source qualifier. You can join relational sources which r coming from different sources also. |
| 6. In which conditions we cannot use joiner transformation (Limitations of joiner transformation)? Answer: Both pipelines begin with the same original data source. Both input pipelines originate from the same Source Qualifier transformation. Both input pipelines originate from the same Normalizer transformation. Both input pipelines originate from the same Joiner transformation. Either input pipelines contains an Update Strategy transformation. Either input pipelines contains a connected or unconnected Sequence Generator transformation. |
| 7. What are the settings that u use to configure the joiner transformation? Answer: Master and detail source Type of join Condition of the join |
| 8. What are the join types in joiner transformation? Answer: -Normal (Default) -Master outer -Detail outer -Full outer |
| 9. What are the joiner caches? Answer: When a Joiner transformation occurs in a session, the Informatica Server reads all the records from the master source and builds index and data caches based on the master rows. After building the caches, the Joiner transformation reads records from the detail source and perform joins. |
| 10. What is the look up transformation? Answer: Use lookup transformation in u’r mapping to lookup data in a relational table, view, synonym. Informatica server queries the look up table based on the lookup ports in the transformation. It compares the lookup transformation port values to lookup table column values based on the look up condition. |
| 11.Why use the lookup transformation ? Answer: To perform the following tasks. Get a related value. For example, if your source table includes employee ID, but you want to include the employee name in your target table to make your summary data easier to read. Perform a calculation. Many normalized tables include values used in a calculation, such as gross sales per invoice or sales tax, but not the calculated value (such as net sales). Update slowly changing dimension tables. You can use a Lookup transformation to determine whether records already exist in the target. |
| 12. What is Datadriven? Answer: The informatica server follows instructions coded into update strategy transformations within the session mapping determine how to flag records for insert, update, delete or reject If u do not choose data driven option setting, the informatica server ignores all update strategy transformations in the mapping. |
| 13. What are the options in the target session of update strategy transformation? Answer: Insert Delete Update Update as update Update as insert Update else insert Truncate table |
| 14.What is the default source option for update stratgey transformation? Answer: Data driven. |
| 15. Describe two levels in which update strategy transformation sets? Answer: Within a session. When you configure a session, you can instruct the Informatica Server to either treat all records in the same way (for example, treat all records as inserts), or use instructions coded into the session mapping to flag records for different database operations. Within a mapping. Within a mapping, you use the Update Strategy transformation to flag records for insert, delete, update, or reject. |
Also Read :
1. What is the difference between Informatica PowerCenter and Informatica Cloud?
2.What is a Synchronization task in Informatica?
3.What is a Runtime environment in Informatica?
4.What is Check In Check Out in Informatica powercenter (Versioning)
Informatica interview questions and answers | Informatica interview questions and answers