Develop Reference

GreenDao - Android - OnUpgrade not being called (Encrypted Database)

I'm using GreenDao 3.2.2 for my DB,
On my first run on creating Entities via #tags everything worked ok.
Now I am editing the gradle schema to higher versions because I added some props to a table:
greendao {
schemaVersion 4
}
However the OpenHelper onUpgrade method is never called, thus my project is always crashing because some columns are not found.
Application class
//Init DB
UpgradeHelper helper = new UpgradeHelper(this, ENCRYPTED ? "db-encrypted" : "db", null);
Database db = ENCRYPTED ? helper.getEncryptedWritableDb("app-cipher") : helper.getWritableDb();
daoSession = new DaoMaster(db).newSession();
OpenHelper class
public class UpgradeHelper extends DaoMaster.OpenHelper {
public UpgradeHelper(Context context, String name, SQLiteDatabase.CursorFactory factory) {
super(context, name, factory);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
//never gets called
Log.i("greenDAO", "Upgrading schema from version " + oldVersion + " to " + newVersion);
//do migrations
}
}
am I missing something?

Got it!!! After hours of searching and reading GreenDAO code I understood the problem.
The problem is that getEncryptedWritableDb creates another kind of DB that does not extends SQLiteDatabase. So even when the EncryptedHelper gets the onUpgrade method, my helper class didn't catch it because it fell into another signature.
The solution was simply using the other signature that receives a DAO Database interface:
public void onUpgrade(Database db, int oldVersion, int newVersion) {
Log.i("greenDAO", "Upgrading schema from version " + oldVersion + " to " + newVersion + " by migrating all tables data");
//do migration
}
of course I needed to update all my Migration methods to receive a Database object instead of a StandardDatabase

Manually executing sql query in Android

I already have a database in my app using a 3rd party library. The library doesn't seem to have drop table functionality. So I was thinking to directly change it using SQLiteOpenHelper API. Is this possible?
I have created a class that extends SQLiteOpenHelper and give it the same db name as the one used in the library.
public class SqliteDatabaseHelper extends SQLiteOpenHelper {
// Database Info
private static final String DATABASE_NAME = "myDatabase";
private static final int DATABASE_VERSION = 1;
private Context context;
public SqliteDatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
this.context = context;
}
#Override
public void onCreate(SQLiteDatabase db) {
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
L.w("old: " + oldVersion + ", " + "new: " + newVersion);
if (oldVersion != newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + "deals_latest");
onCreate(db);
L.w("drop it like it's hot");
}
}
}
And I initialize it in Application class, just to see if it reflects the db class I created.
SQLiteDatabase db = new SqliteDatabaseHelper(this).getReadableDatabase();
L.w("version: " + db.getVersion());
L.w("path: " + db.getPath());
SqliteDatabaseHelper helper = new SqliteDatabaseHelper(this);
helper.onUpgrade(db, 1, 2); // this line suppose to invoke the drop table query
When running the app, onUpgrade() method doesn't seem to be called.
Mind you, I have never had any experience in using the native SQLite helper, so I have no idea what is going on here. My objective is just to see if the query in onUpgrade is executed or not. But the table still exists in the database.
How do I get around this?

The SQLiteOpenHelper class helps to manage versions of your own database.
It does not make sense to use it for a database that is managed by third-party code.
Just open the database directly with openDatabase().

How to upgrade sqlite database on android?

I implemented a ContentProvider for my android app and it works very well but when I make some changes to the schema, the database doesn't seem to be upgraded.
I have the following code in my SQLiteOpenHelper :
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
Log.w(DEBUG_TAG, "Upgrading database. Existing contents will be lost. ["
+ oldVersion + "]->[" + newVersion + "]");
db.execSQL("DROP TABLE IF EXISTS " + TABLE_TUTORIALS);
onCreate(db);
}
If I update my app with a new schema then all my inserts fail BUT if I uninstall the old version and install the new version of the app then everything works fine. So I guess that onUpgrade() is never called. What do oldVersion and newVersion refer to? Do I need to specify the version anywhere?

SQLiteOpenHelper has a version argument, if you increment onUpgrade should be called:
public SQLiteOpenHelper (Context context, String name, SQLiteDatabase.CursorFactory factory, int version)
For example I have the following class and if I increment dbVersion it is called:
public class DBHelper extends SQLiteOpenHelper {
private SQLiteDatabase m_Db;
public DBHelper(Context context, String dbPath, int dbVersion) {
super(context, dbPath, null, dbVersion);
...
m_Db = getWritableDatabase();
}
...
}

I am getting error while Version creating my database

I am getting following error while Version Creating My Database.
01-18 12:08:01.157: ERROR/AndroidRuntime(3079): Caused by: java.lang.IllegalArgumentException: Version must be >= 1, was 0
Please Help me regarding this.

Each database you create has a version number. That way you can keep track of them if you upgrade the application (perform necessary database changes for the upgrade on existing data). The version number must start from 1.
If you look at the following code:
private static class OpenHelper extends SQLiteOpenHelper {
OpenHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
#Override
public void onCreate(SQLiteDatabase db) {
db.execSQL("CREATE TABLE " + TABLE_NAME + "
(id INTEGER PRIMARY KEY, name TEXT)");
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
Log.w("Example", "Upgrading database, this will drop tables and recreate.");
db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
onCreate(db);
}
onUpgrade will handle all necessary database upgrades. Sometimes you'll opt to just destroy (drop) the current database and create a new one.

it seems you have set previous version as 0, remove your app from phone, reinstall it, make sure new version is greater then previous one.

onUpgrade database Android version number not increasing

I am trying to update my database in my Android application. When I update the version number, onUpgrade gets called, but the version number doesn't increase, so every time I access the database, onUpgrade gets called. Here is my code:
private final static int DB_VERSION = 8;
public DataBaseHelper(Context context) {
super(context, DB_NAME, null, DB_VERSION);
this.myContext = context;
}
#Override
public void onCreate(SQLiteDatabase db) {
Log.d(TAG, "in onCreate");
try {
copyDataBase();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
Log.d(TAG, "in onUpgrade. Old is: " + oldVersion + " New is: " + newVersion);
myContext.deleteDatabase(DB_NAME);
Log.d(TAG, "the version is " + db.getVersion());
db.setVersion(newVersion);
Log.d(TAG, "the version is " + db.getVersion());
onCreate(db);
}
Anyone know why this is happening?

Don't try to manually set the version. (This is all taken care of.)
Don't try to delete the database. You're in the middle of upgrading it, and it shouldn't really surprise you that manually setting the version of a database you've just deleted doesn't work very well.
All you should do in onUpgrade is make the changes needed to the structure of the tables. If you want to do this by deleting the current tables (NOT the database) and then re-creating them, then that's fine.
If you need to preserve the data in your tables, have a look at this question for suggestions on how to do it:
Upgrade SQLite database from one version to another?

I ended up adding another database to the assets folder. I know its not the best solution, but it works. When the app is upgraded this time, it just writes the new database - it has a new name - instead of the old one. I check if the old one exists and if it does, I delete it.