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Updating/Maintaining SQLite database after each App Release Xamarin Forms

This is my first time working on a Xamarin App and I am new to the app development world so I need some help figuring out this process.
Currently I run a php web service that generates some SQL files that I run in DB Browser and I get a database file which I then put into my Assets and Resources Folder. Using each platform's API I copy the database into a writable folder and use that to run my queries.
I followed this really helpful tutorial and it worked perfectly fine.
https://medium.com/#hameedkunkanoor/creating-a-sqlite-databse-and-storing-your-data-in-your-android-and-ios-application-in-xamarin-2ebaa79cdff0 .
After the "initial" setup I store a timestamp in a local table and and the next time the user opens the app I pass that timestamp and retrieve data that is older than that timestamp. The I update that timestamp and continue the process. That data is sent back in JSON format and make the updates to the tables.
My only concern is if a new version were to come out where I add a new table or a new column which is not present in the current version of my Database, how should I take care of those update Web Service calls? Is there a way of monitoring my DB version? I read somewhere where I could just ignore the new data that is not present already, like table or columns, but I'm not really sure how to do that.
I also saw that if I call CreateTable on my current tables I could potentially update them?
Also for future reference each time I develop a new app would I need to regenerate a new database file to store in the assets/resources folder? Is there a more automated process for this? Along with monitoring the version of my database?
Any Help/Tutorials/Suggestions would be greatly appreciated.

You have to remember that CreateTable it's already doing the columns update for you, because internally it calls a method called MigrateTable which you can see here for further clarification: https://github.com/praeclarum/sqlite-net/blob/master/src/SQLite.cs#L562.
However you could have to handle more advanced modification to your database, like adding triggers or something similar.
In that case i suggest you to perform modifications manually.
In Xamarin Forms i've ended up with this:
https://gist.github.com/matpag/b2545cc22c8e22449cd7eaf6b4910396
Could not be the best strategy ever but seems to work for me.
Summarizing :
You have to save the database version in an internal flag of the SQlite database called user_version accessible with PRAGMA keyword.
Every time you get the database connection, you have to perform a check and see if the current database version is the same as the app last database version.
If not you need to perform a database update and set the new current version.
Reference here.

How handle Previous Sqlite Db Data while updating Apk in android?

I have already uploaded one apk file for one of the project, now i am updating apk with updated column in my database table,so i dont want to loss previous apk db table data.
so please help me out from this.
Thanks,
Dhiraj

Use SQLiteOpenHelper and implement onUpgrade(). You are passed the old and new database schema versions, and you can then perform an in-place modification of your database structure (e.g., run ALTER TABLE statements using execSql() on the supplied SQLiteDatabase instance).

Update application SQLite database created by Assets DB

I have Database in my application which is created by just coping the SQLite database file from the assets folder but now in the next release I want to update the database without losing the previous data.
Is there any Logic or way to copy the previous data and create a new database through SQLiteOpenHelper so that in near future I will not face this problem.
Thanks

Use this gist
In the OnUpgrade method, copy your previous data from the old database.
In the doUpgrade method, use your copied data to update the new database.

Previous data will be kept by default when users update to a new version. but you must keep in mind there will be new users never get a former version app. So you should add complete database in the assets folder.

android sqlite on application update

I hava an android application which consists sqlite database in the assets folder.
In the DB I have several tables, which one of them is user data (which is updated over time by using the application - when the user installs the application this table is empty).
The other tables store data that I update.
The question is: when a user gets an updated version of my application (with sqlite database in the assets folder) from the market, I need to keep the data the user updated by using the application, but i do want to update the other tables (which consist my data).
What is the correct way to do it?
Thank You :)

Keep a version number for each change and implement the onUpgrade method for the possible combinations. See more in the javadoc for SQLiteOpenHelper

Since you said your tables are empty when the Database is first created, it shouldn't be necessary to add the Database from the /assets-folder.
Instead, you can use a SQLiteOpenHelper, which offers an onCreate()-method that can do the initial table-creation (an add some example data if necessary).
If you then update your app, you simply increase the Database-version and the onUpgrade()-method is called, where you can then perform the Database update.
See this other question: Run some code when user update my app
If your app comes with a huge Database and inserting entry's in the SQLiteOpenHelper isn't the right way to go, you can still check if the Database already exists and then do the updating (through the onUpgrade()-method) and keep the users data.

Android: SQLite Database. Do we need to create it?

I've been going through some tutorials on working with sqlite databases and they all seem to create a new database, tables, etc on the first run of the application. Is this necessary? What if I already have a pre-built database sitting in the assets folder when the application is installed? Can I not simply just open the connection to said database and start using its information or is there a specific reason everyone wants to create it using sql on first launch?

This question comes up frequently. Try this tutorial to use an existing database on Android:
http://www.reigndesign.com/blog/using-your-own-sqlite-database-in-android-applications/

You can't use database file which sits in assets folder directly as SQLite database, since this file would not be usual file located in common filesystem. E.g. you can have only readonly access to it. So the only your option is to copy those database from assets folder to device's filesystem.
To handle database creation for the first time and accessing it there's special helper class SQLiteOpenHelper. Read about it here. Specifically look in SQLiteOpenHelper.onCreate() - where should sit database creation (or copying from assets folder as in your case)

It's been quite sometime since I last worked with SQLite databases (in Android) but I believe that when they write CREATE statements, they always do so with the IF NOT EXISTS condition (i.e., CREATE (DATABASE|TABLE) IF NOT EXISTS...).
I don't know what you'll use SQLite for but I believe they do that in Android "just to make sure". That is, if it's the user's first time to run the app, the DB/Tables must be created first else app goes bonkers. Otherwise, they are (probably) created already and this case will be handled by the IF NOT EXISTS clause and they just go ahead and create a connection with the existing DB. Win-win.
(If, for some reason, it is not the user's first time to use the app and the DB isn't there, it will just be created again. But that's obvious isn't it? ;) )

If you just link with preexisting database it wont bind to your system. So there may be failures. Creating db at first run is the most appropriate way to work with db.