问如何在nodejs中组织与DB的交互？

EN

var MariaSQL = require('mariasql');
var db = new MariaSQL();
var queries = {
    getUserByID : 'SELECT * FROM user WHERE id=:id',
    getUserByUsername : 'SELECT * FROM user WHERE username=:username'
};

module.exports = {
    connect : function(config){
        db.connect({
            host : config.maria.host,
            user : config.maria.user,
            password : config.maria.password,
            db : config.maria.db
        });
        db.on('connect', function() {
            console.log('Successfully connected to DB');
        })
        .on('error', function(err) {
            console.log('Connection error: ' + err);
        })
        .on('close', function(hadError) {
            console.log('Client closed');
        });
    },
    executeQuery : function(queryName, queryData, callback){
        var data = queryData || {};
        var result = [];
        var error;
        if(queryName in queries){
            var pq = db.prepare(queries[queryName]);
            db.query(pq(data))
            .on('result', function(res) {
                res.on('row', function(row) {
                    result.push(row);
                })
                .on('error', function(err){
                    error = err;
                })
                .on('end', function(info) {
                    //console.log('Result finished successfully, numRows = ' + info.numRows + ', insertid=' + info.insertId);
                });
            })
            .on('end', function() {
                if(error)
                    callback(error);
                else
                    callback(null, result);
            });
        } else {
            callback(new Error('Wrong query with name = ' + queryName));
        }
    }
};