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How does Z ORDERING improve query performance in large datasets?

SQLmedium0.3 min readPremium
Frequency
Low
Asked at 1 company
Category
487
questions in SQL
Difficulty Split
130E|271M|86H
in this category
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1,863
across 7 categories
Asked at these companies
Puma
Key Concepts Tested
partition
Expert AnswerPremium
57 wordsInterview-ready
**Z-ordering** (Z-order curve): Colocates related data in same files. Multi-column filter (e.g., region + date) can skip more files vs. single-column partitioning. **Delta**: OPTIMIZE table ZORDER BY (col1, col2). **Why**: Improves file pruning; columnar still scans selected files. **Order**: High-filter columns first. **Combine**: Partition by date + Z-order by (region, user_id)....
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