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Article0 replies4,124 followingPosted 16 Jul 2025, 20:09 UTC132K views1,671 votes

Taming Unpredictable Latency in Azure SQL Database with OPTION (RECOMPILE)

Learn how to solve unpredictable query performance in Azure SQL Database caused by parameter sniffing using the OPTION (RECOMPILE) hint to stabilize latency.

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Tasadduq Burneyowner

Started16 Jul 2025, 20:09 UTC

Level 38Owner35,775 rep points

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Article0 replies3,363 followingPosted 28 Sept 2025, 06:55 UTC118.7K views1,876 votes

Django ORM: Choosing Between select_related and prefetch_related for N+1 Query Problems

Django's select_related and prefetch_related solve N+1 queries differently: JOINs for single-valued relationships, separate queries joined in Python for collections. A practical guide to choosing, combining, and verifying the fix with a worked article-listing example.

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n-plus-one

django query-optimization

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Article0 replies3,249 followingPosted 02 Feb 2026, 16:50 UTC31.4K views3,909 votes

MySQL Composite Indexes: Column Order, the Leftmost Prefix Rule, and When They Stop Helping

Composite indexes beat multiple single‑column indexes for multi‑column filters, but only if column order respects the leftmost prefix rule and equality columns come before the range column.

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composite-index indexing query-optimization

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Article0 replies2,496 followingPosted 12 Feb 2026, 20:33 UTC18.1K views4,624 votes

MongoDB Compound Index Order: Treat Key Sequence as an Interface, Not a Tuning Knob

A compound index is an ordered path, not a bag of fields. Here is how key order decides which MongoDB queries get an IXSCAN, and how to verify it with explain executionStats.

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database-performance indexing

mongodb

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Article0 replies1,790 followingPosted 03 Sept 2026, 19:05 UTC146.2K views4,436 votes

Covering Indexes in MySQL: When the Index Is the Whole Answer

A covering index lets InnoDB answer a query entirely from the index tree, skipping per-row lookups. Here's how to design one, verify it with EXPLAIN, and weigh the write cost.

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innodb indexing query-optimization

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Article0 replies4,611 followingPosted 28 Aug 2025, 10:47 UTC12.6K views2,155 votes

Choosing Between select_related and prefetch_related in Django ORM

Learn when to use select_related versus prefetch_related to cut N+1 queries in Django, with a concrete example and verification steps.

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django performance query-optimization

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Article0 replies862 followingPosted 20 Mar 2026, 03:10 UTC48.4K views2,201 votes

Optimizing MongoDB Queries with Compound Indexes: Applying the Equality‑Sort‑Range Rule

Use a compound index in Equality‑Sort‑Range order to let MongoDB filter, sort, and apply range predicates in one scan. Verify with explain and watch write overhead.

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mongodb query-optimization esr-rule

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Article0 replies753 followingPosted 03 May 2026, 04:20 UTC97.7K views4,746 votes

Speeding Point‑in‑Polygon Queries with Detaspace Geo‑Partitioning

Discover how Detaspace’s Geo‑Partitioning feature can cut point‑in‑polygon query times from minutes to sub‑second by tiling data into spatial blocks. Follow a step‑by‑step example, weigh the storage trade‑off, and get ready to boost your geospatial workloads.

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geospatial data-partitioning

detaspace

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Article0 replies2,850 followingPosted 26 Aug 2025, 03:12 UTC112.8K views2,673 votes

Diagnosing DuckDB Memory Spills and External Sort Diagnostics

When DuckDB queries fail with out-of-memory errors or sudden slowdowns from external sorting, this guide walks you through recognizing the condition, diagnosing with EXPLAIN ANALYZE, and applying targeted fixes.

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memory-limits

duckdb external-sort