Developer launches free interactive SQL practice tool for data engineering interviews

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A developer has built a free, browser-based tool designed to help candidates prepare for data engineering interviews through hands-on SQL practice. Unlike static resources that simply display answers, the tool requires users to write actual SQL queries and receive instant feedback on their logic. The current version includes around 10 questions covering common interview topics such as window functions, duplicate detection, and sequence gap analysis. The creator plans to expand the tool with Python, dbt, and Spark-related questions in the coming weeks. The project is open source, and the developer is actively seeking feedback and suggestions from both job seekers and interviewers.

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