is there any javascript object database??
Something like http://www.db4o.com/ but for javascript?
thanks
HTML5 includes an embedded SQL database. You could write a tiny ORM around it to deal only in objects.
Checkout ActiveJS and specifically ActiveRecord. It does not use the HTML5 Web SQL database currently, but has plans on supporting that.
Also a timeless post (no year anywhere), mentions JStorm but I'm not too familiar with it.
Is it needed for client-side, or server-side?
If you are looking for server side object oriented database for JavaScript, you can check http://wakandadb.org/ They have complete end-to-end solution for web / mobile development using JS as complete stack, check that at http://www.wakanda.org/
Wakanda is good NoSQL JS object database, but it might not be good for cloud based apps that need to soon scale out. Scaling out with will be an issues, which is a plus point with MongoDB, Cassandra or CouchDB kind of databases, but these data bases are not object-oriented, most of them are simply JSON stores.
Take a look at IndexedDB. They refer to it as an "object store" all the time, and I think it can store arbitrary objects. Don't use WebSQL since it is now discontinued and doesn't support all JavaScript objects. See also Wikipedia article.
Related
EDIT#2 - The replies until now (after 2 days) are personal opinions and preferences and not an analysis of the various options that an offline-phoneGap app has to store simple data easily across all relevant devices. As such I haven't accepted any answer, but I am following this question.
I am a little confused about which format of persistent data I should be looking into for a PhoneGap web app I'm building. I've been researching this but things are not clear given my mediocre requirements.
The app is an educational app with about 100 or so multiple choice questions and some memorization games attached.
The app once downloaded can remain offline.
It is for all phonegap supported devices.
The only data that I want to read and write is the user's performance, number of times wrong in total, per card etc and any high scores for games.
This is all very basic information and could be held in very simple js objects.
I would like it to be a fairly simple solution and very easy to maintain/repeat.
What would be my best option? The phonegap file api? json/lawnchair? local-storage? cookies? Would there be a way to 'update' the app and keep it as an object in the javascript? websql? sqilite? Storage API?
Some of these seem overkill.
EDIT
Are there differences in devices and I should do some device detection and use different technologies?
I personally like localStorage. It's straight forward and works great for most situations.
If you are just recording the data you mention above, localStorage would be perfect. I would just seralise your data objects by turning them into a string using say JSON.stringify(), then when pulling it back in use JSON.parse() to turn it back into a useable JS object.
How about try out my library http://dev.yathit.com/ydn-db/getting-started.html backed by IndexedDB (excellent performance, query by index scan), WebSQL (good performance, SQL query) or localStorage (fair performance, no query, get by key, 2.5 MB limit).
db = new ydn.db.Storage('test-store');
db.put('store1', {test: 'Hello World!'}, 123);
req = db.get('store1', 123);
req.done(function(record) {
console.log(record);
});
High performance while still go easy.
Don't like library dependency, take raw source code at https://bitbucket.org/ytkyaw/ydn-db
It looks like these are good ones, though I haven't tried them.
localForage
PouchDB
If you're using the ionic framework which uses AngularJS, I like ngStorage. This one I have tried and it's awesome.
I use localStorage to keep my persistent data, but it is somehow not reliable. I have seen some data lost, but I don't know why. But my persistent data usage is not that critical so I don't mind these inconsistencies.
But your case seems more important. I would store my persistent data in Documents folder, with File API.
Phonegap has local storage support for SQL Lite
http://docs.phonegap.com/en/2.2.0/cordova_storage_storage.md.html#Storage
Sorry I don't have more info. I was interested in this topic and happened to come across it.
I'm programming a browser application (html5+websockets+css3+js preferred) that enables users to concurrently access (read, write) attributes of the same object. To create a real-time experience I'd like to use optimistic synchronization. I read about Timewarp and Trailing State algorithms and I wonder if there is a javascript library, which already implements these or similar algorithms.
I found this question, but unfortunately it was not answered yet. XSTM only supports pessimistic synchronization as it seems.
Do you have any idea for me?
I am working on a realtime HTML5 web browser application now too. Maybe my choice of weaponry could inspire you...who knows, so I am using:
Frontend:
KnockoutJS -it takes care of displaying data which I send to every connected client in JSON(view models), you can easily subscribe to changes in the client data and push the changes back to server, though I am having problems displaying pages with knockoutjs on mobile browsers
on serverside I run custom made server based on Fleck
Since JSON is my favourite data format, I ditched SQL databases in favour of [RavenDB][2], which stores data almost exactly as they are sent via websocket protocol and also it is pretty quick
I have to develop a website for mobile phones and I am using html5 and javascript. Can I access/insert into server database using html5 and javascript only without using asp, php or any other server side language.
Yes it is. You will however need a backend database with a HTTP interface. One of which is MongoDB which has a REST interface.
More info here http://www.mongodb.org/display/DOCS/Mongo+Extended+JSON
No, you can't, and if you could then you would be insane to do so as it would allow everybody to make arbitrary SQL queries.
Html and Javascript are the Front end side languages, it not advisable to use those languages features to connect to database. Later it would be very tough to maintain it and enhance it.
ALWAYS THINK IN FUTURE PERSPECTIVE, else your code becomes obsolete
instead you can use any scripting language like php to connect to database.
Since you wanted to create a website, obviously PHP and mysal will be always available to you at NO COST.
Use javascript and maybe you may not want to connect to mysql... Try .csv formats and excel... It's good if you are not storing sensitive information.
I would like to see a decent example of a mobile web app using the Sencha framework with a client side DB accessed with SQLite. I'm currently digesting JqTouch and kinda get the binding method used there from reading Jonathon Stark's "iPhone apps" book, but cant find any examples of accessing Senchas features ie listed elements with SQLite. The DB will be small; 30 records, with about 5 fields, mostly numeric, a few of them calculated. All the math is done in javascript and I have that part working (in dash code). I need to add, delete, and edit the records.
Any pointers or examples would be very much appreciated. I'm an old dog trying to learn new tricks. Thanks
Sencha is client-side Javascript, so your application actually runs on top of Safari. That means you can forget about accessing (or installing) your own SQLite database from within the browser sandbox.
Having said that, you want to learn some new tricks, so why dont you read up on localStorage and DOM Storage. Basically the HTML5 specification allows for offline database storage based on SQLite (imagine relational database cookies). There is 1 per domain and they can be up to 5MB in size. I believe the iPhone supports this as well.
Here are some links: Introduction some API Information and a nice little blog entry by a chap called Ben Lister
Your client side code (i.e. Sencha/Javascript) would not access the SQLLite database. It will either need to read JSON or XML from the server. You'll need server side code to read the data from the database and format it in a way that your Sencha data readers will understand.
What are you using server side? If it's PHP you should look into MDB2
I had very good experience integrating Lawnchair library with Sencha Touch. Take a look at their guide, it's very easy.
Looks like there is a SQLite proxy available for sencha 2 now. http://market.sencha.com/addon/sqliteproxy-
Check out this thread on the Sencha Forums - it's a user created proxy for SQLite which I've successfully used to put data into a SQLite DB. The proxy comes with an example, but I might try and make a slightly more complicated one at some point.
Sencha's local storage doesn't take advantage of SQLite via the JavaScript API in the browser, but does use local key:value storage and has it's own way of referencing data to make it pseudo relational. This is still part of the WebDB spec, which is probably still SQLite under the hood if I had to guess. It's more persistent than a cookie or session, regardless.
You can also receive XML/JSON from a server over JSONP or Ajax if you're on the same domain, create a model to handle that data as well and bind it to a local store so that your data is available offline.
I am currently looking for an intelligent best practice solution for the following problem. Within a web page, I want to make use of data that is currently organised in some MySQL tables.
Problem: I cannot access the database from the webserver, so I am not able to query the data using SQL. Therefore, I thought to transform the data into something JavaScript can handle (e.g. JSON) and perform all the operations on the data on client-side.
Doing SQL-like queries on an object will probably be kind of hard, even if those I need will probably be easy (simple SELECTs). Is there a elegant way to do that? Some nice little javascript library?
Thanks in advance for your ideas.
Best practice would (of course) be to put some kind of link (even if not a direct one) between the database and the web server.
For SQL in the browser, though, there's the TrimQuery library, basically a mini-SQL engine written in JavaScript for use on the browser. You would output the "tables" as arays of objects using JSON (as you indicated), and then query it via TrimQuery's SQL support.
But if you can't access the database from the web server, I assume you'll be making a mostly-static copy of the data as an admin procedure and placing it on the webserver. That being the case, you may well be better off determining your usage patterns in your web app and then formatting the data into useful objects as part of the DB->web server copy operation. But if you really need ad-hoc queries into the data, TrimQuery may be a route you could use.
You can try JSINQ:
http://jsinq.codeplex.com/
which is a Javsascript LINQ implementation. It allows to "query" json object with linq expressions (then in a sql-like way).