ETL is an acronym for "extract, transfer and load" which is a process that companies use to extract and store electronic data. An ETL developer is an information technology professional who works to ensure that this is done in an efficient and secure manner with the job role usually involving building, testing and maintaining these databases. Interview questions for an ETL developer should test the knowledge and experience of internet technology and data systems.
What are the responsibilities of an ETL developer?
If the developer has experience then the question could be rephrased by asking what their responsibilities were in their last role. This gives the interviewer a clear indication of how their knowledge and prior experience compares to the requirements of the vacant role. This can be followed up by asking questions about previous projects they have worked on, any challenges they faced and how they overcame them.
Explain the ETL process
This allows the candidate to explain the steps involved in the ETL process in logical order. ETL is the extraction, transforming, loading process where data is extracted from the source. The steps described should be define the source, define the target, create the mapping, create the session then create the workflow.
Explain partitioning and different types
Partitioning is the process of dividing information into smaller units to make extracting and transferring easier and more efficient. The candidate should be able to discuss increasing the number of partitions, how to configure the partitioning information and how the server redistributes data across partition points. Types of partitioning include horizontal, vertical, passthrough, range, hash and key, list and composite.
What are push and pull ETL strategies?
Push and pull strategies determine how data comes from the source system to the ETL server. The candidate should be able to describe both functions. Push is when the course system sends data to the ETL server. Pull is when the ETL server gets the data from the source system.
- 20 of the funniest online reviews ever
- 14 Biggest lies people tell in online dating sites
- Hilarious things Google thinks you're trying to search for