Assists with writing SQL queries for project databases. Orchestrates schema lookup via subagent to keep main context clean. Use when asked to query data, debug database issues, or explore the schema.
Write correct SQL queries by looking up the schema first, never guessing table or column names.
Follow this three-step pattern to keep the main context clean while getting accurate schema information.
Use the Task tool to investigate the schema before writing any query. This keeps column-level detail out of the main conversation.
Pass the subagent this prompt template (fill in [database] and [question]):
Investigate the [database] database schema to help answer: [question]
1. Read schema://[database] for the relationship overview
2. For each relevant table, call search_objects with the table name
3. Return: table names, relevant columns (with types), JOIN paths between tables, any enum values needed
Keep the summary compact -- only include columns relevant to the question.
The subagent will return a compact summary with table names, column types, JOIN paths, and enum values.
Use the subagent's summary to write the query. Apply the gotchas below.
Run with execute_sql against the target database.
PostgreSQL folds unquoted identifiers to lowercase. Every camelCase column must be double-quoted:
-- Wrong
SELECT createdAt, partnerId FROM collaborations;
-- Correct
SELECT "createdAt", "partnerId" FROM collaborations;
Prisma models often have different names than the underlying SQL tables. When in doubt, use search_objects with the Prisma model name — it returns the SQL table name.
Prisma enums map to PostgreSQL custom types. Query them as quoted strings:
SELECT * FROM orders WHERE status = 'COMPLETED' LIMIT 10;
Use search_objects to see available enum values for a column.
| ID | Environment | Access | Use When |
|---|---|---|---|
| local | Development | read-write | Local development and testing |
| staging | Staging | read-only | Verifying staging data |
| production | Production | read-only | Debugging live issues |
Default to local for exploration. Use production only when debugging live issues.