explain_query
Read-only
Explains SQL query execution plans with cost estimates. Optionally runs query for real statistics or simulates hypothetical indexes to compare performance.
Instructions
Explains the execution plan for a SQL query, showing how the database will execute it and provides detailed cost estimates.
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| sql | Yes | SQL query to explain | |
| analyze | No | When True, actually runs the query to show real execution statistics instead of estimates. Takes longer but provides more accurate information. | |
| hypothetical_indexes | No | A list of hypothetical indexes to simulate. Each index must be a dictionary with these keys: - 'table': The table name to add the index to (e.g., 'users') - 'columns': List of column names to include in the index (e.g., ['email'] or ['last_name', 'first_name']) - 'using': Optional index method (default: 'btree', other options include 'hash', 'gist', etc.) Examples: [ {"table": "users", "columns": ["email"], "using": "btree"}, {"table": "orders", "columns": ["user_id", "created_at"]} ] If there is no hypothetical index, you can pass an empty list. |
Output Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| result | Yes |