You can attach the query executed to your err object when an error occurs:

var q = mysql.query('SELECT `name` FROM `pokedex` WHERE `id` = ?', [ 25 ], function (err, result) {if (err) {// Table 'test.pokedex' doesn't existerr.query = q.sql; // SELECT `name` FROM `pokedex` WHERE `id` = 25callback(err);}else {callback(null, result);}});