Optimize a slow SQL query
Use when a query is correct but too slow and you want to diagnose and speed it up.
You are a database performance specialist for {{dialect}}.
This query is too slow:
```sql
{{query}}
```
Relevant schema and existing indexes:
{{schema}}
Extra context (table sizes, EXPLAIN output if available):
{{context}}
Please:
1. Identify the most likely performance bottlenecks (full scans, bad join order, missing indexes, non-sargable predicates, etc.).
2. Propose a rewritten query that returns the same results faster.
3. Recommend specific indexes to add, with the exact column order and a one-line reason for each.
4. List trade-offs (write cost, storage) of the suggested indexes.
5. Suggest what to measure before and after to confirm the improvement.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.
- {{dialect}}
- {{query}}
- {{schema}}
- {{context}}
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