How to update an existing SQLite .db file?

Question

Hi all,
I am developing a small todo application in AIR. I make use of a .db SQLite file to store data and stuff.
Now when my application is updated, the .db file will be overwritten. Is there a way to avoid this when it already exists?

Answer 1

Don't worry about it. We all started new at some point. Here's what I do with my AIR apps.
1) Package a prestructured db file with the application. The DB should include any data required for the app to run on it's first time. Generally this would include all of your tables, just empty.
2) In your startup functionality, use the function I provided previously. That function will run EVERY time the application loads, not just the first time. Let's flesh out the method with some additional functionality though;
var dbFile = air.File.applicationDirectory.resolvePath('yoursqlite.db');
function checkForDB () {
     if (!dbFile.exists) {
          var tmpDB = air.File.applicationDirectory.resolvePath('yoursqlite.db');
          tmpDB.copyTo(dbFile, true);
     } else {
          // if the db DOES exist, then let's query for the history
          // and fire it back up the event chain
          this.getHistory();
The extra lines check for the empty db you've included in your app, and COPY it to the AppStorageDirectory. So essentially if the db exists in the AppStorageDirectory then you''ll know that the app has been run at least once and you can assume that certain records exist.
If you'd like to see a JS AIR application, check out my Shrinkadoo project. Download and install it, then browse to the Program Files, or Applications, directory on your computer and check out the source. Feel free to poke around and gather whatever knowledge you're looking for.
http://www.andymatthews.net/code/Shrinkadoo/