Execute Query
execute_queryRun SQL queries on PostgreSQL, MySQL, or SQLite databases using connection strings to retrieve or modify data.
Instructions
Run a query to database
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| db_type | Yes | ||
| connection_string | Yes | ||
| query | Yes |
Implementation Reference
- src/tools.ts:134-156 (handler)The handler function that creates a Sequelize connection based on db_type and connection_string, optionally blocks write operations, executes the provided SQL query, and returns the results as JSON text.
async ({db_type, connection_string, query}) => { const sequelize = new Sequelize(connection_string, { dialect: db_type, }) if (!enableWriteOperations) { const writeOperations = ['INSERT', 'UPDATE', 'DELETE', 'CREATE', 'ALTER', 'DROP'] if (writeOperations.some((operation) => query.toUpperCase().includes(operation))) { throw new Error('Write operations are not enabled') } } const [results] = await sequelize.query(query) return { content: [ { type: 'text', text: JSON.stringify(results), } ], } }, - src/tools.ts:128-132 (schema)Zod input schema defining parameters: db_type (postgres/mysql/sqlite), connection_string, and query.
inputSchema: { db_type: z.enum(['postgres', 'mysql', 'sqlite']), connection_string: z.string(), query: z.string(), }, - src/tools.ts:123-157 (registration)Registration of the 'execute_query' tool using McpServer.registerTool, including title, description, input schema, and handler function.
server.registerTool( 'execute_query', { title: 'Execute Query', description: 'Run a query to database', inputSchema: { db_type: z.enum(['postgres', 'mysql', 'sqlite']), connection_string: z.string(), query: z.string(), }, }, async ({db_type, connection_string, query}) => { const sequelize = new Sequelize(connection_string, { dialect: db_type, }) if (!enableWriteOperations) { const writeOperations = ['INSERT', 'UPDATE', 'DELETE', 'CREATE', 'ALTER', 'DROP'] if (writeOperations.some((operation) => query.toUpperCase().includes(operation))) { throw new Error('Write operations are not enabled') } } const [results] = await sequelize.query(query) return { content: [ { type: 'text', text: JSON.stringify(results), } ], } }, )