Event before install app. Update database in exesting app


Hi all ! Could anyone suggest please, if exist way to listen installing new build and do alter table in SQLite if needable ?


You could make a const DATA_VERSION and save that in the DB and compare it every start of the app:


const DATA_VERSION:number = 1; //Increment this number whit each version that you alter your db structure 

function onStart() {
 if(DATA_VERSION > /*version number that is stored in the db*/ ){
  migrate(/*version number that is stored in the db*/).then( _ => {
   /*set the version number that is stored in the db to DATA_VERSION*/
   /* start the app like normal */
 } else {/* start the app like normal */}
function migrate (oldversion:number):Promise<any> {
 //Migrate the data, oldversion tells you from which version.

As alternative for const DATA_VERSION you could use the build number, but you won’t change your db structure every update, right?

PS: If you want to migrate from an version that is already in production you could also check is const DATA_VERSION is set.

And DATA_VERSION is just a random name, you could use every name you choose.


user5555, thanks a lot.


Hi ,

Is there any event for update app from test flight ? i need to change the database schema while update the app



There is no such event, how should it work anyway? Try the solution from above and if it doesn’t works for you tell us more about your special needs.