Question

I have a project with a set of classes that are responsible for their respective database tables.

Each table managing class contains CRUD methods that follow the pattern of get connection, run crud operation, close connection:

public class PersonManager {

    SQLiteDatabase db;
    DbAdapter dbAdapter; //This is a subclass of SQLiteOpenHelper

    public void addPerson(Person person)
    {
        ContentValues contentValues = new ContentValues();
        contentValues.put("email", person.email);
        contentValues.put("first_name", person.firstName);

        db = dbAdapter.getWritableDatabase();
        db.insert("person", null, contentValues);
        db.close();
    }

    ...other crud/utility methods omitted...
}

Now that I am upgrading my database via onUpgrade(), I run into database locked issues.

The exact error message follows:

CREATE TABLE android_metadata failed
Failed to setLocale() when constructing, closing the database
android.database.sqlite.SQLiteException: database is locked

It appears that onUpgrade is either meant to:

1 run db.execSQL() calls or
2 use helper classes that use onUpgrade()'s SQLiteDatabase rather than their own

It would be much easier to use my table managing classes to migrate data in onUpgrade() than db.execSQL() statements, or rewrite all my CRUD methods to take onUpgrade()’s SQLiteDatabase.

Am I setting up my database access correctly? If the above code follows the correct pattern, what should I do to fix this issue?

Thanks!

Answer 1

I didn’t get any answers, so I asked on a dev hangout.

According to the Android Developer Hangout Team, onUpgrade is only meant for structure alterations, not really for data migration/manipulation.