The original title is "Data Engineer LeetCode: What to Grind and What to Skip"

Short summary

Data engineering interviews have shifted from algorithm puzzles (binary trees, DP, graphs) to SQL fluency—window functions, CTEs, join-grain awareness, NULL handling. Yet most candidates waste 80+ hours grinding LeetCode when 35-50 targeted problems suffice. Focus on SQL patterns and pipeline design thinking, the actual gatekeeping skills that separate junior from intermediate engineers.

• •Most data engineering interviews test SQL (window functions, CTEs, join-grain awareness) and data manipulation, not binary trees or graph algorithms
• •Candidates waste 80+ hours grinding LeetCode when 35-50 focused problems covering SQL patterns suffice for most roles
• •SQL window functions, ROW_NUMBER/RANK/DENSE_RANK, NULL handling, and deduplication are the actual gatekeepers separating junior from intermediate engineers

Generated with AI, which can make mistakes.