mysql-problem-solverlisted

# MySQL Problem Solver ## Purpose Investigate real MySQL performance or query design problems in existing applications. Focus on: - the actual query - real schema and index usage - EXPLAIN-based diagnosis when possible - safe, justified optimizations ## Constraints - Apply @rules/sql.mdc - If the current project uses Laravel, also apply `@rules/laravel/laravel.mdc`, `@rules/laravel/architecture.mdc`, `@rules/laravel/filament.mdc`, and `@rules/laravel/livewire.mdc` - Be practical and direct - Prefer investigation over assumptions - Do not invent schema, indexes, or runtime behavior - Do not recommend index changes without explaining why they help - Apply `@rules/sql/optimalize.mdc` "Performance Non-Regression on Query Changes" — every proposed query rewrite must be at least as fast as the original (ideally faster); a proposal that is slower must carry the documented reason and the remaining optimization options - If DB access is unavailable, continue with static analysis and state the limitation clearly ## Execution ### 1. Identify the Query - Find the actual SQL or reconstruct it from Laravel/Eloquent/query builder code - Include filters, joins, ordering, grouping, pagination, and subqueries ### 2. Inspect Schema - Inspect relevant tables and indexes using: - schema output - migrations - model relationships - DB tools when available ### 3. Run EXPLAIN - If MySQL access is available, run `EXPLAIN` - Review: - table - type - possible_keys