Informatica is a powerful data integration tool that is widely used in the industry for its robust capabilities. As a result, many companies seek skilled Informatica professionals to handle their data integration needs. If you are preparing for an Informatica interview, it is essential to be well-versed in the common Informatica interview questions. This article will provide you with a comprehensive list of Informatica interview questions to help you ace your interview.
1. Can you explain the difference between a session and a workflow in Informatica?
A session is a unit of work that reads data from a source, transforms it, and loads it into a target. On the other hand, a workflow is a container that groups multiple sessions together. Workflows can be scheduled to run at specific times or triggered by events.
2. What are the different types of transformations in Informatica?
Informatica provides various types of transformations, including:
- Aggregator: Aggregates data from multiple rows into a single row.
- Joiner: Combines data from two or more sources based on a join condition.
- Filter: Filters out rows based on a specified condition.
- Sorter: Sorts data based on one or more columns.
- Router: Routes data based on a specified condition.
- Expression: Performs calculations or manipulations on data.
3. What is the purpose of a mapping in Informatica?
A mapping is a visual representation of the data flow between sources and targets. It defines the transformation logic and the relationship between source and target objects. Mappings are created using the Mapping Designer and are used to generate sessions and workflows.
4. Explain the difference between a source and a target in Informatica.
A source is the origin of the data, such as a database table, flat file, or an API. A target is the destination where the data is loaded, such as a database table, flat file, or an application. Sources and targets are defined in the Informatica repository and are used in mappings to define the data flow.
5. What is a lookup in Informatica, and how does it work?
A lookup is a transformation that retrieves data from a lookup table based on a match condition. It is used to enhance the accuracy of data by ensuring that it is consistent with the lookup table. Lookup tables can be stored in a database, flat file, or a cube.
6. What are the different types of lookups in Informatica?
Informatica provides three types of lookups:
- Normal Lookup: Retrieves data from a lookup table based on a match condition.
- Outer Join Lookup: Retrieves data from a lookup table even if there is no match in the source data.
- Inner Join Lookup: Retrieves data from a lookup table only if there is a match in the source data.
7. Explain the purpose of the Mapping Editor in Informatica.
The Mapping Editor is a graphical tool used to create and edit mappings. It allows users to design the data flow, add transformations, and define the relationship between source and target objects. The Mapping Editor is an essential part of the Informatica Designer toolset.
8. What is the role of a repository in Informatica?
The repository is a centralized storage for all Informatica metadata, including mappings, workflows, sessions, and sources/targets. It ensures that all team members have access to the latest information and promotes collaboration.
9. How can you optimize the performance of an Informatica session?
There are several ways to optimize the performance of an Informatica session:
- Use appropriate transformations and optimize the mapping design.
- Optimize the source and target configurations, such as setting the appropriate block size and buffer size.
- Use partitioning to distribute the workload across multiple nodes.
- Monitor the session performance and make necessary adjustments.
10. What are the different types of repositories in Informatica?
Informatica supports two types of repositories:
- File-based repository: Stores metadata in a file system.
- Database-based repository: Stores metadata in a database, such as Oracle or SQL Server.
By familiarizing yourself with these Informatica interview questions and their answers, you will be well-prepared to showcase your expertise and land your dream job.
