query_rw

Execute SQL queries that can modify data or schema in MotherDuck.

Description

The query_rw tool executes SQL against your MotherDuck databases, including operations that change data or schema. For cross-database queries, use fully qualified names: database.schema.table (or database.table for the main schema).

Input Parameters

Parameter	Type	Required	Description
database	string	No	Database context for the query. Required when the statement targets database objects. Optional for account-level operations.
sql	string	Yes	DuckDB SQL statement to execute

Output Schema

Same as query:

{
  "success": boolean,
  "columns": string[],           // Column names (on success)
  "columnTypes": string[],       // Column types (on success)
  "rows": any[][],               // Query results (on success)
  "rowCount": number,            // Number of rows returned (on success)
  "error": string,               // Error message (on failure)
  "errorType": string            // Error type (on failure)
}

Limits

• Result limit: Maximum 2,048 rows and 50,000 characters. Results exceeding these limits will be truncated with a truncation message.
• Query timeout: 55 seconds. Queries exceeding this limit will be cancelled server-side and the tool will respond with an error message.

Example Usage

Insert rows:

Insert a new customer 'Acme Corp' with id 100 into my_database.customers

{
  "database": "my_database",
  "sql": "INSERT INTO customers (id, name) VALUES (100, 'Acme Corp')"
}

Update and delete:

In my_database, set status to 'shipped' for all orders in the orders table where status is 'pending', then delete the old log entries from audit_log

The AI assistant can call query_rw with the appropriate UPDATE and DELETE statements (or multiple calls if the client requires one statement per call).

Create table:

Create a table my_database.main.events with columns id (BIGINT), name (VARCHAR), created_at (TIMESTAMP)

{
  "database": "my_database",
  "sql": "CREATE TABLE main.events (id BIGINT, name VARCHAR, created_at TIMESTAMP)"
}

Account-level operations (database optional):

Create a new database called reporting

{
  "sql": "CREATE DATABASE reporting"
}

For account-level operations, omit database and pass only sql.