Diego Dupin added a comment - 2023-09-08 15:09 If no warning logger is set, those warning will still be written on console. Here is an example of use : const mariadb = require( 'mariadb' ); const winston = require( 'winston' );   const logger = winston.createLogger({ level: 'info' , transports: [ // - Write all logs with level `error` and below to `error.log` // - Write all logs with level `info` and below to `combined.log` new winston.transports.Console({ filename: 'error.log' , level: 'error' }), new winston.transports.Console({ filename: 'combined.log' }) ] });   const pool = mariadb.createPool({ host: 'mydb.com' , user: 'myUser' , password: 'myPwd' , logger: { network: (msg) => logger.silly(msg), query: (msg) => logger.info(msg), error: (err) => logger.error(err), warning: (msg) => logger.warn(msg), } });