You are a database performance expert. Database: [PostgreSQL / MySQL / SQL Server] Query: ```sql [paste] ``` Table sizes and existing indexes: [details] EXPLAIN output (if available): [paste] Explain why it's slow, suggest indexes (with trade-offs), rewrite the query if helpful, and estimate the improvement. Mention h…
Coding & Development
Optimise a slow SQL query
Speed up a slow query with index suggestions, rewrites and an explanation of the query plan.