On 13 Sep 2012, at 3:13pm, Jean-Denis Muys <jdm...@cmd-informatique.com> wrote:
> I work on an application that uses an SQLite database as it's binary document > format (with a custom extension). Now we want to develop a Web App variation > of that application, that should be able to read and write those > documents/databases. Since the Web App is written in Javascript, I am now > looking for a Javascript implementation of the SQLite library. This can't be done entirely in JavaScript, since JavaScript running in a web browser has no way of getting at files on your hard disk. This is to prevent the programmers of a web site spying on your computer's files. > I have used the C SQLite library in the past, so I know about using SQLite > from C. However, I am just starting with Javascript and Web Apps and I am > quite a newbie on that side (Other people on the team are experienced, but I > have been asked to work on the SQLite integration). There are ways you can allow JavaScript to access data inside a file on a web server. The standard way is to write a shim in PHP or some similar language. The PHP code runs on the web server and uses PHP's SQLite3 library to access databases. You ask it to execute a SQLite command, and it returns the results in JSON (or some other) format. So for instance https://myserver.com/databases/doSQLCommand.php?file=money.sqlite&command=SELECT * FROM transactions WHERE id=123 might return a page of application/json type containing {id: 123, trandate: "20030205", amount: 274.53} Of course in real life you're more likely to pass the parameters using POST than GET. Your JavaScript code asks the shim for the data using an XMLHttpRequest and uses JSON.parse() to turn the results into an array or an object. There are, of course, many security concerns with such a setup, so most shim programs check to see that they're being called only from their own server, by a program they recognise, running on a computer they recognise. I sometimes use a setup like this, though my shim returns the requested results as only a small part of the stuff it returns, the rest being things like error messages and last-insert-id and stuff like that. Simon. _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
