Answer
Parallel skew occurs when workers process uneven workloads. Detected via EXPLAIN with parallel details and fixed with better partitioning or query rewrites.
Quick Answer
Parallel query skew: one worker gets much more work than others, becoming the bottleneck. Happens with data skew (some partition ranges have far more rows), poor parallelization of certain operations, or when parallel workers can't evenly split the work. Detect with EXPLAIN ANALYZE - look for workers with very different row counts. Fix: use hash partitioning, improve statistics, or accept that parallelism doesn't help for that query.
S
SugharaIQ Editorial Team
Verified Answer
This answer has been peer-reviewed by industry experts holding senior engineering roles to ensure technical accuracy and relevance for modern interview standards.
Want to bookmark, take notes, or join discussions?
Sign in to access all features and personalize your learning experience.
Source: SugharaIQ