Data Warehouse Administrator interview questions

A Data Warehouse Administrator is responsible for managing and overseeing the warehouse environment, which includes design, implementation, maintenance, and security of the data warehouse.

ETL stands for Extract, Transform, Load. It's the process of extracting data from various sources, transforming it to fit operational needs, and loading it into a data warehouse.

Ensuring data integrity involves implementing validation checks, conducting routine audits, and using data cleansing techniques to maintain accuracy and consistency.

Optimizing query performance can be achieved through indexing, partitioning, query rewriting, using complex views and ensuring proper database tuning.

Challenges include handling large volumes of data, ensuring data quality, managing data integration from disparate sources, and maintaining system performance and scalability.

Data security can be handled via access control, encryption, auditing, regular patching and updates, and ensuring compliance with data protection regulations like GDPR.

Common tools and technologies include SQL Server, Oracle, IBM DB2, Apache Hadoop, Amazon Redshift, and ETL tools like Informatica and Talend.

Regular backup schedules, automated backup systems, testing recovery processes, and ensuring backups are stored securely offsite are some of the practices followed.

Capacity planning involves analyzing growth trends, assessing future requirements, optimizing storage, and ensuring scalable infrastructure to accommodate increasing data volumes.

Metadata in data warehousing is crucial for data management as it provides data documentation, ensures data accuracy, and acts as a directory to help users find the data they need.