Android sqliteopenhelper data table structure upgrade

Recently, I met a new requirement in the project , You need to add a field in the local cache , Because the user cache is saved in tables according to the group , When updating database upgrade , Finding the to be modified indicates that it is dynamically generated , After continuous efforts and online reference , Finally a solution has been found .

The main logic is still put in customization SQLiteOpenHelper Class onUpgrade In the method , We according to the db Parameters can get all the data tables , Because the table names have certain rules when dividing tables , Therefore, it can be modified uniformly according to this rule . The following is the author's implementation logic , For reference .

public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
	// Different database versions should have different processing logic , At present, only this upgrade is available 
	if (oldVersion == 1) {
		// Query all data table names 
		Cursor cursor = db.rawQuery("select name from sqlite_master where type='table' order by name", null);
		while (cursor.moveToNext()) {
			String name = cursor.getString(0);
			if (!TextUtils.isEmpty(name) && name.startsWith("users_")) {
				// Get the target data table according to the matching rules , Then perform the corresponding operation , This is just a new field 
				db.execSQL("ALTER TABLE " + name + " ADD COLUMN aliasName text");
			}
		}
		// Finally, don't forget to close cursor
		cursor.close();
	}
}