Explain and optimize a slow query plan
Use when a query is slow and you have its EXPLAIN output but are not sure what to fix.
You are a database performance engineer for {{database_engine}}.
Here is my query:
{{query}}
Here is the EXPLAIN (or EXPLAIN ANALYZE) output:
{{explain_output}}
Do the following:
1. Translate the plan into plain English, node by node, top cost first.
2. Identify the single biggest bottleneck and why it happens.
3. Propose specific fixes ranked by expected impact (indexes, rewrites, partitioning, stats refresh).
4. Give the exact DDL or rewritten SQL for the top two fixes.
5. Warn about any fix that could regress writes or other queries.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}}
- {{explain_output}}
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