Complete and continue
ETL Testing: Interview Guide
Interview Questions on ETL and ETL Concepts
What do you understand about ETL? (4:19)
What does ETL testing operations include? (1:39)
What are the popular ETL tools available in the market? (1:56)
Interview questions on Data Warehouse Concepts
Why Data Warehouse is implemented? (5:26)
What are different Data Warehouse architectures which a project can have? (12:22)
What is the use of Staging in a Data Warehouse architecture? (4:23)
What is a Data Mart? (1:47)
Is it mandatory to have Data marts in the Data Warehouse architecture or projects? (1:24)
What is the need of the DataMart in a project? (4:55)
Where does the Data Mart fit into in the overall Data Warehouse architecture? (5:11)
What is OLAP? (5:54)
What are the structural differences between an OLTP and OLAP system? (10:34)
What are Dimensions? (2:48)
What are Confirmed Dimensions? (6:38)
What are Fact Tables? (2:05)
What are Additive Facts? (1:45)
What are Semi-Additive Facts? (2:28)
What are Non-Additive Facts? (1:30)
Explain what is Grain of Fact? (2:17)
What is a Star schema design? (5:23)
What is Snow Flake schema design? (3:25)
What is Operational Data Store [ODS] ? (8:41)
Interview questions related to tables and database in the project
How ETL Testing is different from database testing? (4:21)
Which type of schema is used and why? (2:08)
How many tables are there in your project? (6:54)
What were the tables used in your project? (0:59)
Which were the columns in the tables? (0:33)
How many records does your sources and targets have? (2:22)
Explain different queries used in the project? (0:47)
Have you performed Type 2 validations in your project? (0:47)
What are the challenges faced during testing? (1:36)
How many facts, dimensions and reference tables are in their in your project? (2:31)
How many facts and dimension tables and what were those and Which were the columns in facts and dimension tables? (2:52)
What is Data Sensitivity? (0:54)
How to identify Fact, Dimension, Reference tables based on data? (4:38)
How to check all transactions data, database updates and data flow for accuracy? (2:34)
What is Reconciliation? Have you tested it in your project? (3:16)
How to validate all error are captured and rejection records are available for validations and reporcess? (6:39)
How are the exit and entry criteria defined? (1:55)
What is an Aggregate function? Name a few common aggregate functions? (5:41)
What is a surrogate key in a database? (4:01)
Interview questions on Data Validations
Where does the data validations happen? (1:58)
What is Data Cleansing and Data Scrubbing? (4:07)
What are DataType and DataLength Validations? (3:31)
What are the approaches followed to insert new data file validations? (2:17)
What validations are done in Incremental Loads? (1:28)
Interview questions related to project/application
What areas are covered under finance domain for ETL testing projects? (5:40)
Is the test data created and loaded by the development team? (2:31)
What are the areas where there is a possibility of defects in the Data Warehouse project? (3:15)
What are the documents used in a project and where are the validations defined? (5:15)
Who is responsible for generating the different kinds of documents in the project/application? (8:52)
What is a test case document? (2:54)
How are Bugs or defects managed in your project? (4:05)
What were the details in each project document? (1:47)
What was the complete process followed in your project? (3:06)
Can you explain about the number of downstream systems available in your project? (3:27)
How to test end to end integration of system? (3:12)
Interview questions on RCA (Root Cause Analysis) and UAT Support
Did you perform any Root Cause Analysis (RCA) for issues in your project? (5:03)
What are the steps to prepare test data for UAT (Poduction like)? (5:51)
How did you support UAT? (0:53)
Interview questions related to BI/Reporting
What is the difference between ETL and BI tools? (2:13)
How many down stream systems are there for your application/project? (1:30)
What is Ad-Hoc Reporting? (1:49)
How to validate BI Reports functionality? (3:20)
Interview questions on Data Modelling concepts
What are some of the basic concepts to consider during Data Modelling? (5:07)
Interview questions on Master Data Management (MDM)
What is MDM and what is the need for it in an enterprise and how is it setup? (5:16)
Interview questions on Slowly Changing Dimensions (SCD)
Have you performed SCD Type 2 Validations in your project? (4:54)
How is the SCD setup done at ETL layer? (4:27)
What are the challenges faced with respect to SCD? (2:34)
What is ETL automation and what are the areas in which you have done the automation? (2:42)
Interview questions on Informatica Power Center Tool
What do you understand by the term ‘transformation’? (2:36)
What are the different types of Transformations available in Informatica? (0:47)
What do you understand by Active and Passive Transformations? (5:42)
What is lookup transformation and when is it used? (7:22)
Explain what are the differences between Unconnected and Connected lookup? (4:57)
What is a Worklet? (3:12)
What is a Work Flow? (7:27)
Explain the terms − mapplet, session, mapping, workflow − in an ETL process? (4:35)
Explain what is tracing level and what are the types? (4:47)
Interview questions on UNIX commands
What are the situations where you had to use the UNIX commands in ETL testing? (11:14)
What are your responsibilities as an ETL Tester?
Understanding logical flow of the applicaion or project (3:50)
Analysis of the specifications provided by the clients (2:45)
Approve requirements and design specifications (1:18)
Create and Maintain the test stratergy document (1:13)
Design the Test Cases as per the Test plan (1:16)
Estimate the efforts required to design the test cases and excute the project (1:23)
Tracability of requirements to test cases (1:10)
Define Exit and Entrace criteria (0:53)
Create Test Plan and Play a Key Role (1:50)
Test Data Creation (4:31)
Creating and Maintaining Reusable Scripts and Execute Test Scripts (1:20)
Execute and RCA and Review (1:47)
Client Co-ordination and Incorporate UAT Test cases and Identify Bugs (1:44)
Final note on the overall roles and responsibilities of the ETL Tester (3:41)
Interview questions on Unit Testing
What is unit testing? who will do this? (2:39)
What are the advantages of performing the Unit Testing? (2:41)
To Be Added
What is the difference between data warehousing and data mining?
Explain the difference between DDL, DML, and DCL statements?
What is an Operator in SQL? Explain common operator types?
What are the common set operators in SQL?
What is the difference between Minus and Intersect? What is their use in ETL testing?
Explain ‘Group-by’ and ‘Having’ clause with an example?
What is the difference between surrogate key and primary key?
What are the common ETL Testing scenarios?
What is data purging?
Name a few checks that can be performed to achieve ETL Testing Data accuracy?
Which SQL statements can be used to perform Data completeness validation?
What is the difference between shortcut and reusable transformation?
What is Self-Join?
What do you understand by Normalization?
Explain what are ETL Mapping Sheets and what is the use of them?
Can you mention few test cases and explain them?
Can you list few ETL bugs which are possible and which you have created?
What are Cubes?
What are Virtual Cubes?
What is Denormalization?
What is the difference between Severity and Priority?
Whats the difference between Incremental Load and Initial Load?
How do you validate source and target tables are correct?
What is order by?
What are the ETL TESTING Points to explain in the interview?
What are the GUI based ETL tools?
What are programmatic based ETL tools?
What are the different sources of Source systems of Data Warehouse?
What does a Mapping document contains?
What is a Work Flow?
Lecture content locked
If you're already enrolled,
you'll need to login
Enroll in Course to Unlock