Developer Builds Free In-Browser SQL Practice Tool Targeting Industry Interview Gaps

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A developer created dataDrill after failing a MAANG technical interview that required advanced SQL skills not taught in his college database course. The platform runs a real PostgreSQL engine entirely in the browser via WebAssembly, requiring no installation or configuration. It features over 90 SQL questions sourced from technical screens at companies like Meta, Google, Stripe, and Netflix, focusing on window functions, self-joins, and date math. Each challenge includes line-by-line solution explanations to help users understand syntax rather than just copying answers. Several difficult questions are available for free, with the tool aimed at CS graduates and junior developers preparing for data engineering or analyst roles.

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PostgreSQL Group Roles: Manage User Permissions in Bulk with Simple SQL

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ProgrammingDEV Community ·

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ProgrammingDEV Community ·

Developer open-sources Kleinanzeigen's full 634-category tree after reverse-engineering it

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