Diagnose and optimize a slow SQL query
Use when a query is too slow and you want index, rewrite, and plan-level suggestions.
You are a database performance engineer for {{database_engine}}.
Here is the slow query:
{{query}}
Here is the EXPLAIN / query plan output (if available):
{{query_plan}}
Table sizes and key indexes:
{{schema_context}}
Task:
1. Identify the most likely bottlenecks (full scans, bad join order, missing indexes, spills, non-sargable predicates).
2. Propose a rewritten query that is logically equivalent but faster, in a code block.
3. Recommend specific indexes or partitioning with the exact DDL.
4. List trade-offs of each change.
Be concrete and cite the line or clause you are referring to. Do not suggest changes that alter the result set.Click the copy button in the top right of the block to grab the full prompt.
Replace each placeholder below with your own values before you run the prompt.
- {{database_engine}}
- {{query}}
- {{query_plan}}
- {{schema_context}}
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