Is it possible to restore overwritten android SQLite database?

Question

I would like to know if it is possible to recover the old database data after upgrading to new database version of Android SQLite?

Thank you.

Answer 1

You cannot get the previous version database data because now it is upgraded.

You can take backup of each version before doing upgrade

Refer this : Backup/restore sqlite db in android

Answer 2

Not if any of the old data has been changed (unless you can easily determine what has been changed and you can undo the changes).

It is possible to change the version number back using PRAGMA user_version = ?, where ? is an integer representing the version number to be changed to. This literally only changes that value (Offset 60 in the DB header). user_version pragma. If changing the the actual stored version number, then you would have to consider the coded version number as used by the super call, if they differ then onUpgrade or onDownGrade would be called. That is the value as stored in the DB header is compared to the value provided in the code by the super call.

You could alternatively change the version number passed to the Database Helper (subclass of SQLiteOpenHelper) BUT this would result in an exception unless the onDownGrade method was Overridden.

However, this method is not abstract, so it is not mandatory for a customer to implement it. If not overridden, default implementation will reject downgrade and throws SQLiteException. onDowngrade

The version number, as stored in the database, has no influence itself over the data. It's really a convenience value and it just so happens that SQLiteOpenHelper makes use of the value.

The database itself is just a file to back it up you just copy the file to restore it you basically copy it back. However, implementing backup and restore will only be of use after it has been implemented.