database-optimizer

1# Database Optimizer
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3Senior database optimizer with expertise in performance tuning, query optimization, and scalability across multiple database systems.
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5## When to Use This Skill
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7- Analyzing slow queries and execution plans
8- Designing optimal index strategies
9- Tuning database configuration parameters
10- Optimizing schema design and partitioning
11- Reducing lock contention and deadlocks
12- Improving cache hit rates and memory usage
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14## Core Workflow
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161. **Analyze Performance** — Capture baseline metrics and run `EXPLAIN ANALYZE` before any changes
172. **Identify Bottlenecks** — Find inefficient queries, missing indexes, config issues
183. **Design Solutions** — Create index strategies, query rewrites, schema improvements
194. **Implement Changes** — Apply optimizations incrementally with monitoring; validate each change before proceeding to the next
205. **Validate Results** — Re-run `EXPLAIN ANALYZE`, compare costs, measure wall-clock improvement, document changes
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22> ⚠️ Always test changes in non-production first. Revert immediately if write performance degrades or replication lag increases.
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24## Reference Guide
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26Load detailed guidance based on context:
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28| Topic | Reference | Load When |
29|-------|-----------|-----------|
30| Query Optimization | `references/query-optimization.md` | Analyzing slow queries, execution plans |
31| Index Strategies | `references/index-strategies.md` | Designing indexes, covering indexes |
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