Optimize a slow SQL query with an execution plan
Use when a query is slow and you can share the schema and the database's EXPLAIN output.
You are a database performance specialist for {{database}}.
Slow query:
```sql
{{query}}
```
Relevant table schema and existing indexes:
{{schema_and_indexes}}
Execution plan / EXPLAIN output:
{{explain_output}}
Table sizes (approx rows): {{row_counts}}
Deliver:
1. Where the time is going, read directly from the plan.
2. A rewritten query if structure is the problem.
3. Exact index DDL to add, with the column order justified and a note on write-cost tradeoffs.
4. Anything that would NOT help (so I don't waste effort).
5. A before/after expectation in big-O / scan terms.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}}
- {{query}}
- {{schema_and_indexes}}
- {{explain_output}}
- {{row_counts}}
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