Introduction
Informatica is an American software development company founded in 1993. It has its headquarters in Redwood City, California. Informatica is a leading software company specializing in data integration, quality, management, and cloud solutions. Established in 1993, Informatica provides various tools designed to help organizations manage, integrate, and transform vast amounts of data from various sources into useful insights.
The most well-known product of Informatica is Informatica PowerCenter, a powerful data integration platform widely used for extract, transform, and load (ETL) processes. It enables businesses to aggregate, cleanse, and move data between different systems, making it essential for data warehousing and business intelligence initiatives.
We have collected a few Informatica interview questions that will help you crack the Informatica interview and land your dream job. These Informatica interview questions will also help in understanding various concepts of Informatica.
Informatica Basic Interview Questions
1. What is Informatica PowerCenter?
Informatica PowerCenter is a tool used for extraction, transformation, and loading (ETL) tool. These tools are used in building enterprise data warehouses. The components within Informatica PowerCenter help users to connect, fetch, and process data from various sources and transform it as per business requirements, and load it into a target data warehouse. Users can, for instance, connect to an Oracle or SQL Server database, or both, and integrate the data from two databases into a third system.
2. What are the components of Informatica?
The components of Informatica includes:
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PowerCenter Designer: A tool for designing and developing data integration mappings
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PowerCenter Workflow Manager: A tool for scheduling and executing data integration workflows
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PowerCenter Workflow Monitor: A tool for monitoring the execution of data integration workflows
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PowerCenter Repository Manager: A tool for managing the Informatica repository, which stores metadata about data sources, targets, and mappings
- Informatica Integration Service: A service that executes data integration mappings
3. What are data types in Informatica?
The data types in Informatica are:
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Numeric: Integer, decimal, float, double
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Character: String, char
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Date and Time: Date, time, timestamp
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Boolean: True, false
- Binary: Binary data
4. What is Lookup transformation?
It is used to look up data in a relational table through mapping. Any relational database's lookup definition is imported from a source that has a tendency to connect clients and servers.
5. What is the meaning of Lookup transformation?
The primary use of Lookup transformation is to find the source qualifier, a target, or other sources to get the relevant data or information. Various types of files can be searched in the Lookup transformation. The multiple lookup transformations can be used in mapping and are compared with the lookup input port values.
6. Name the different types of ports that create the lookup transformations.
The different types of ports that create the lookup transformation are
- Input port
- Output port
- Lookup port
- Return port
7. How many repositories are created in the Informatica workflow manager?
In Informatica, the Repositories can be created in the workflow manager depending upon the required number of ports.
8. What do you mean by a domain?
A domain is a collection of nodes and services which helps improve data management. It is a collection of resources and services that are managed as a single unit.
9. Can all mappings in the repository be validated simultaneously?
All the mappings in the repository cannot be validated simultaneously since each time, and it can only validate one mapping.
10. Explain the Aggregator transformation.
It allows the execution of calculations involving sums, averages, and other aggregations. On the contrary, expression transformation allows for group calculations.
11. How are duplicate rows deleted from flat files?
Duplicate rows in flat files can be deleted by comparing each row to others and removing any duplicates based on the data in the rows. Also, we can use the sorter transformation and a distinct option to delete duplicate rows.
12. What is the phrase Staging Area?
Transitory tables associated with the workspace or reality tables used to prepare information are in the organizing zone.
13. List the use cases of Informatica?
Informatica is a powerful tool that can be used to address a wide range of data integration and management challenges. By using Informatica, organizations can improve the quality, consistency, and accessibility of their data, which can lead to better business decisions and improved outcomes.
14. What are mapplets?
• It is a reusable object created in the Mapplet Designer
• It consists of a set of transformations and lets us reuse that transformation logic in multiple mappings
15. Explain the difference between Informatica and DataStage.
Below is a table that summarizes the key differences between Informatica and DataStage:
Feature | Informatica | DataStage |
---|---|---|
Comprehensiveness | More comprehensive | Less comprehensive |
User-friendliness | More user-friendly | Less user-friendly |
Cost | More expensive | Less expensive |
Performance | Good | Excellent |
Scalability | Good | Excellent |
Flexibility | Good | Excellent |
Customization | Good | Excellent |
16. What is the role of a repository manager?
An administrative tool used to administrate and manage repository folders, objects, groups, etc., is a repository manager.
A repository manager allows you to navigate multiple folders and repositories and manage groups and user permissions.
17. What are data-driven sessions?
When you set up a session with an update strategy, the data-driven session property instructs the Informatica server to use the instructions coded in the mapping to flag the rows for insert, update, delete, or reject. It can do it by mentioning “DD_UPDATE” or “DD_INSERT”, or “DD_DELETE” in the update strategy transformation.
18. What is the target load order?
Target load order generally specifies the order in which an integration service loads target tables. You can select a target load order based on the source qualifier transformations in a mapping.
In Informatica, you can specify the order in which data is loaded into targets when multiple source qualifier transformations connect to various targets.
19. Differentiate between Mapping and Mapplet.
Mapping |
Mapplet |
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Mapping is a collection of source, target, and transformation. | Mapplet is a collection of only transformation. |
Mapping is developed with different transformations but is not reusable. | Mapplet can re-use with other mapping and mapplets. |
It is developed around what data move to the target and what modification is performed. | It is developed for complex calculations used in multiple mappings |
20. Explain the difference between active and passive transformation.
Transformation can be classified into two types:
Active transformation |
Passive transformation |
---|---|
Here, the number of rows that pass from the source to the target is reduced as it eliminates the rows that do not meet the transformation condition. Additionally, it can change the transaction history or row type. |
Unlike active transformations, passive transformations do not eliminate the number of rows, so all rows pass from source to target without being modified. Additionally, it can maintain the transaction boundary and row type. |
21. Explain the code page compatibility.
Data loss cannot occur when data is moved between code pages, as long as both code pages use the same character set. The target page must contain all characteristics of the source page.
Additionally, if all the characters of the source page are not present on the target page, then it would be a subset, and there will be loss of data loss during transformation as the two code pages are not compatible.
22. How do pre-session and post-session shell commands function?
For a session task, a command task can be called a pre-session or post-session shell command. The user can run it as the pre-session command, post-session command success, or post-session command failure.
The application of the shell commands can be changed or modified based on use cases.
23. How many input parameters can exist in an unconnected lookup?
Various numbers of input parameters can exist in an unconnected lookup. For example, you can provide input parameters like column 1, column 2, column 3, column 4, and so on. But every time, the return value will be one.
24. Describe Expression transformation.
In this form of transformation, values can calculate in a single row before writing on the target. It can use to carry out non-aggregate calculations. Before output results are sent to the target tables, conditional statements can also be tested.
25. What is Joiner transformation?
While a source qualifier transformation can combine data from a common source, a joiner transformation combines two affiliated heterogeneous sources located in different locations.