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SQL Performance Tuning Expert

Diagnoses slow queries and delivers specific optimization strategies including execution plan analysis, indexing, partitioning, materialized views, and query rewriting with implementation-ready SQL.

Platinum
v1.0.10 activationsData & AnalyticsTechnologyexpert

SupaScore

86.7
Research Quality (15%)
8.5
Prompt Engineering (25%)
8.7
Practical Utility (15%)
9
Completeness (10%)
8.5
User Satisfaction (20%)
8.5
Decision Usefulness (15%)
8.8

Best for

  • Diagnose and fix slow-running queries with execution times over 5 seconds
  • Analyze PostgreSQL EXPLAIN ANALYZE output to identify bottlenecks in complex joins
  • Design optimal B-tree and covering index strategies for high-traffic OLTP workloads
  • Rewrite correlated subqueries and CTEs for better optimizer cooperation
  • Implement table partitioning strategies for time-series data exceeding 100GB

What you'll get

  • Execution plan breakdown identifying the most expensive operations with specific index recommendations and CREATE INDEX statements
  • Query rewrite transforming correlated subqueries to window functions with before/after performance comparisons
  • Comprehensive optimization strategy covering missing indexes, query restructuring, and configuration adjustments with implementation priority
Not designed for ↓
  • ×Basic SQL syntax teaching or beginner query writing
  • ×Database schema design or entity relationship modeling
  • ×Database administration tasks like backup, replication, or user management
  • ×Application-level caching strategies or ORM configuration
Expects

Slow query with execution plan (EXPLAIN ANALYZE), table schemas, current indexes, and database engine details.

Returns

Specific optimization recommendations with implementation-ready SQL, performance impact estimates, and execution plan analysis.

Evidence Policy

Enabled: this skill cites sources and distinguishes evidence from opinion.

sql-optimizationquery-tuningexecution-plansindexingdatabase-performancepartitioningmaterialized-viewspostgresqlmysqlexplain-analyzequery-rewritingdatabase-profiling

Research Foundation: 8 sources (3 official docs, 4 books, 1 web)

This skill was developed through independent research and synthesis. SupaSkills is not affiliated with or endorsed by any cited author or organisation.

Version History

v1.0.12/15/2026

Auto-versioned: masterfile quality gate passed (score: 87.0)

v1.0.02/15/2026

Initial release

Works well with

Need more depth?

Specialist skills that go deeper in areas this skill touches.

Common Workflows

Database Performance Analysis Pipeline

Complete database performance optimization workflow from query tuning to infrastructure monitoring setup

sql-performance-tuning-expertDatabase Performance Tunermonitoring-observability-designer

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