Dataset Prototype (WebSQL rquired but will be replaced to IndexedDB.)

dataset.js

(function(un){
	var versions = {}
	, defer = function(context){
		this.fn = {};
		this.context = context;
		this.set = function(key, fn){defer.isF(fn) ? this.fn[key] = fn : defer.noF;};
		this.get = function(key){return defer.isF(this.fn[key]) ? this.fn[key] : defer.noF;};
		this.one = function(key){var fn = this.get(key); delete this.fn[key]; return fn;};
		this.is = function(key){return key in this.fn;};
	}, keygen = function(){
		return 'FN#DS$' + Math.ceil(Math.abs(Math.random()*(new Date())));
	};
	defer.isF = function(fn){return typeof(fn) === 'function' || fn instanceof Function;};
	defer.noF = function(){};
	var DataSet = function(id, cols){
		var that = this, fnkey = this.next = keygen();
		this.id = id || 'DataSet#' + +(new Date());
		this.cols = cols;
		this.defer = new defer(this);
		this.db = window.openDatabase('__DATASET_DB__', '1.0', 'DB for DataSet Framework.', 10*1024*1024);
		this.db.transaction(function(tx){
			tx.executeSql('CREATE TABLE IF NOT EXISTS ' + that.id + ' ('+that.cols.join(',')+')');
			that.defer.one(fnkey).call(that);
		});
	};
	DataSet.prototype = {
		select: function(){
			var that = this, fnkey = this.next = keygen();
			this.db.transaction(function(tx){
				tx.executeSql('SELECT * FROM ' + that.id + '', [], function (tx, results) {
					that.defer.one(fnkey).call(that, results);
				}, DataSet.onerror);
			});
			return this;
		},
		insert: function(){
			var that = this, args = arguments, slots = [], fnkey = this.next = keygen();
			[].forEach.call(args, function(){slots.push('?')});
			if(this.cols.length != args.length){
				throw new Error('cols and arguments are not match.')
			}
			this.db.transaction(function(tx){
				var sql;
				tx.executeSql(sql='INSERT INTO ' + that.id + ' ('+that.cols.join(',')+') VALUES ('+slots.join(',')+')', args, function (tx, results) {
					that.defer.one(fnkey).call(that, results);
				}, DataSet.onerror);
				console.log(sql);console.log(args);
			});
			return this;
		},
		then: function(fn){
			console.log('SET : '+this.next);
			this.defer.set(this.next, fn);
			return this;
		}
	};
	Object.defineProperties(DataSet.prototype, {
		
	});
	DataSet.onerror = function(tx, error){
		if(window.console && console.error){
			console.error(error);
		}
	};

	window.DataSet = DataSet;

})();

example.js

var ds = new DataSet('test', ['code', 'name', 'date']);
ds.then(function(){
    console.log('DB complete.');
}).select().then(function(result){
    console.log(result.rows.length);
}).insert(~~(Math.random()*1024),new Date().toLocaleString(), new Date())
.then(function(){
    console.log('DB insert.');
});