Latest Informatica Interview Questions and Answers
Briefly describe lookup transformation?
Lookup transformations are those transformations which have admission right to RDBMS based data set. The server makes the access faster by using the lookup tables to look at explicit table data or the database. Concluding data is achieved by matching the look up condition for all look up ports delivered during transformations.
Explain the use of aggregator cache file?
Aggregator transformations are handled in chunks of instructions during each run. It stores transitional values which are found in local buffer memory. Aggregators provides extra cache files for storing the transformation values if extra memory is required.
Can one use mapping parameter or variables created in one mapping into any other reusable transformation?
Yes, One can do because reusable transformation does not contain any mapplet or mapping.
How can one identify whether mapping is correct or not without connecting session?
One can find whether the session is correct or not without connecting the session is with the help of debugging option.
What is complex mapping?
Following are the features of complex mapping.
- Difficult requirements
- Many numbers of transformations
- Complex business logic
Explain the difference between mapping parameter and mapping variable?
When values change during the session’s execution it’s called a mapping variable. Upon completion the Informatica server stores the end value of a variable and is reused when session restarts. Moreover those values that do not change during the sessions execution are called mapping parameters. Mapping procedure explains mapping parameters and their usage. Values are allocated to these parameters before starting the session.
How many number of sessions can one group in batches?
One can group any number of sessions but it would be easier for migration if the number of sessions are lesser in a batch.
Explain sessions. Explain how batches are used to combine executions?
A teaching set that needs to be implemented to convert data from a source to a target is called a session. Session can be carried out using the session’s manager or pmcmd command. Batch execution can be used to combine sessions executions either in serial manner or in a parallel. Batches can have different sessions carrying forward in a parallel or serial manner.
How are indexes created after completing the load process?
For the purpose of creating indexes after the load process, command tasks at session level can be used. Index creating scripts can be brought in line with the session’s workflow or the post session implementation sequence. Moreover this type of index creation cannot be controlled after the load process at transformation level.
What is the benefit of partitioning a session?
Partitioning a session means solo implementation sequences within the session. It’s main purpose is to improve server’s operation and efficiency. Other transformations including extractions and other outputs of single partitions are carried out in parallel.
How many repositories can be created in informatica?
There can be any number of repositories in informatica but eventually it depends on number of ports.
What is the difference between a repository server and a powerhouse?
Repository server controls the complete repository which includes tables, charts, and various procedures etc. Its main function is to assure the repository integrity and consistency. While a powerhouse server governs the implementation of various processes among the factors of server’s database repository.
What is meant by a domain?
When all related relationships and nodes are covered by a sole organizational point, its called domain. Through this data management can be improved.
What the difference is between a database, a data warehouse and a data mart?
Database includes a set of sensibly affiliated data which is normally small in size as compared to data warehouse. While in data warehouse there are assortments of all sorts of data and data is taken out only according to the customer’s needs. On the other hand datamart is also a set of data which is designed to cater the needs of different domains. For instance an organization having different chunk of data for its different departments i.e. sales, finance, marketing etc.
What do you mean by Enterprise Data Warehousing?
When the organization data is created at a single point of access it is called as enterprise data warehousing. Data can be provided with a global view to the server via a single source store. One can do periodic analysis on that same source. It gives better results but however the time required is high.