Populate SQLite only once upon installation of UWP app - sqlite

Question

I am developing UWP application using vs studio 2017 version 15.9.6.
I want to use Windows local SQLite database. I want to run an SQL script named mySql.txt when the user first time install the application. I dont want to run it every time when the user run the app as it contain insert statement, which will cause duplicate rows insertion. So I want to run that script only once, preferably in the installation time.
How can I do that? I am very new to UWP and .NET. Please guide me step-by-step if possible.

Answer 1

You can make sure the initialization/seeding is done only once for the app. For that you may utilize ApplicationDate.Current.LocalSettings.
These allow you to write simple data for your application which are bound to your app. Once the user uninstalls the app, these data will be removed as well. This fits your scenario exactly.
Suppose your database initialization code is in the method InitializeDb(). You could use the following to make sure the initialization is done only once:
if (!ApplicationData.Current.LocalSettings.Values.ContainsKey("DbInitialized"))
{
InitializeDb();
ApplicationData.Current.LocalSettings.Values["DbInitialized"] = true;
}
This code first checks if we have initialized the db previously and if not, performs the initialization and stores a flag into app settings to make sure the next time the initialization is skipped.
You can run this code during app initialization, for example in OnLaunched method, or on when the database service is first required.
This is of course the simplest implementation, so you can (and should) add some exception handling, so that if the initialization fails, it can be retried and so on. Also you may want to handle app updates and DB updates - in which case you can use ApplicationData.Current.Version which allows you to track the version of application data and can be used to keep track of DB version as well so you can perform appropriate migrations between versions.
Finally, for even better user convenience, there is also a way to perform the app update steps during updates. See this article for more info.