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Android ORMLite DbHelper onCreate() not called even after uninstall

I'm getting this error when I run my app for the first time after re-install:
android.database.sqlite.SQLiteException: no such table
(This error happens when my app tries to read from the database)
For some reason the onCreate() method in DBHelper is not getting called and therefore the tables are not getting created. I followed the advice from other question and tried calling getWritableDatabase(), also tried a create() call to insert data in some table, but still no luck: onCreate is never called.
I got it to work however by changing the DATABASE_VERSION value to 2. But that doesn't make sense since this is a brand new installation after uninstall.
Also I found that before the SQL read error the database got created but it has only 1 table "android_metadata" (not created by me).
I'm posting some code here for reference
public class DatabaseHelper extends OrmLiteSqliteOpenHelper{
private static final String DATABASE_NAME = "RoutePlanner.db";
private static final int DATABASE_VERSION = 1;
private Dao<Trip, Integer> tripDAO = null;
private RuntimeExceptionDao<Trip, Integer> tripRunTimeDAO = null;
...
}
#Override
public SQLiteDatabase getWritableDatabase() {
return super.getWritableDatabase();
}
public DatabaseHelper(Context context){
super(context, DATABASE_NAME,null, DATABASE_VERSION, R.raw.ormlite_config);
}
#Override
public void onCreate(SQLiteDatabase db, ConnectionSource source) {
try {
Log.i(DatabaseHelper.class.getSimpleName(), "onCreate");
TableUtils.createTable(source, Trip.class);
...
} catch (SQLException ex) {
Log.e(DatabaseHelper.class.getSimpleName(), "Error creating db", ex);
throw new RuntimeException(ex);
}
}

OK, I found the problem, hope this explanations helps others on what NOT to do. The issue was that I had a separate calendar module which I wanted to access my Database. To make things 'simpler' I created a separate DatabaseHelper on that module to access the same SQLite databse as my main module. The existance of the 2nd DatabaseHelper was causing all my issues. Solutions are either join the 2 modules into one, or use a Database Service Provider

Are all databases provided by a SQLiteOpenHelper constructed with the same name within an app guaranteed to be identical?

If multiple activities within an app call the constructor of my SQLiteOpenHelper with themselves as the context argument, can I be sure that they will all access the same database?
For example, let's say I have:
package foo.bar;
public class Activity1 extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
SQLiteDatabase db = new MySQLiteOpenHelper(this).getReadableDatabase();
:
}
}
and
package foo.bar.baz;
public class Activity2 extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
SQLiteDatabase db = new MySQLiteOpenHelper(this).getReadableDatabase();
:
}
}
Here's in the skeleton of my SQLiteOpenHelper subclass:
public class MySQLiteOpenHelper extends SQLiteOpenHelper {
private static final String DATABASE_NAME = "comments.db";
private static final int DATABASE_VERSION = 1;
public MySQLiteOpenHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
:
}
I can't find anything in the documentation that guarantees that the two activities get the same database. On the other hand, I haven't seen any mentions of people getting different databases from contexts within a single application. Are the database paths guaranteed to be identical?

SQLiteOpenHelper has 2 constructors and the second parameter for both of them is the database file name.
If you used the same database file name when using SQLiteOpenHelper from different activities, you will get access to the same database.
This is usually taken care of in the constructor of the inheriting class you create - DATABASE_NAME is a constant:
public MySQLiteOpenHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}

if you do it as the Android folks recommend (http://developer.android.com/guide/topics/data/data-storage.html#db)
Then yes, all activities within an app will see the same database

correct use of SQLiteOpenHelper (and some consultation)

I have the following code below.
I am creating a database in my application that uses SQLiteOpenHelper.
I have couple of concerns and would appreciate some consults.
Direct answers for these were not found on stack overflow as they might be subjective.
1 - I will be using this database from several activities. However I am not planning on making this a singleton to avoid leaks, but rather I will be getting the getWritableDatabase() and getReadableDatabase() inside each method. I plan on doing a db.close() inside each activity's onDestroy() .Is this advisable ? given my app has couple of activites and is not a huge app.
2 - I am not following and DAO model, nor I am using a different class for every table.
The way I see it, I don't need to. Do I ?
3 - (A question rather than consult)
In the code below, I am not creating a database of the form
private SQLiteDatabase database;
So all the references to the database (from my activities) are being done via the methods in the same subclassed SQLiteOpenHelper, therefore I am referencing the physically created database directly via getWritableDatabase and getReadableDatabase.
Do I need to create an instance of SQLiteDatabase and use it ? Even inside the subclass of SQLiteOpenHelper ?
Below is the code.
public class DbHelper extends SQLiteOpenHelper
{
private static final String DATABASE_NAME = "myDbName";
private static final String DATABASE_TABLE = "myTable";
private static final int DATABASE_VERSION = 1;
private Context ctx;
public DbHelper(Context context)
{
super(context, DATABASE_NAME, null, DATABASE_VERSION);
this.ctx = context;
}
#Override
public void onCreate(SQLiteDatabase db)
{
db.execSQL("CREATE TABLE myTable(_id INTEGER PRIMARY KEY, title TEXT);");
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion)
{
//nothing here now. maybe later.
}
public void insertTitle(String title)
{
ContentValues titleCV = new ContentValues();
titleCV .put("title", title);
getWritableDatabase().insert(DATABASE_TABLE, null, titleCV );
}
public void getTitles()
{
Cursor result = getReadableDatabase().rawQuery("SELECT _id, title FROM myTable", null);
while (result.moveToNext())
{
int id = result.getInt(0);
String titleGotten= result.getString(1);
}
result.close();
}

Q1
If you have a scenario within your app that have two parallel threads accessing the database, use a single instance of the SQLiteOpenHelper (singleton or member in the Application or whatever). If not you don't need to.
about calling db.close(), if it is in the onDestroy(), then it's fine.
Q2
a DAO is an abstraction layer to ease maintaining and scaling your project. If you are not going to scale or maintain your code (upcoming releases or something), then I suppose you don't need one.
Q3
You don't need to create an instance of SQLiteDatabse. when you call getReadableDatabase() or getWritableDatabase(), SQLiteOpenHelper creates and maintains an instance. The same instance is used the next time you call getReadable\WritableDatabase().
let me know if you still have questions.

step 1: make a staic instace of SqliteOpenHelper
step 2: you never close conexion to database, sqlite manage itself the sequencial access to write or read :)
private static ControladorBBDD instancia;
my class: public class ControladorBBDD extends SQLiteOpenHelper {
default :
private ControladorBBDD(Context ctx_p) throws Exception {
super(ctx_p, DB_NAME, null, DATABASE_VERSION);
try {
ControladorBBDD.ctx = ctx_p;
DB_PATH = ctx.getDatabasePath(DB_NAME).getAbsolutePath();
String myPath = DB_PATH;// + DB_NAME;
this.createDataBase();
db = SQLiteDatabase.openDatabase(myPath, null,
SQLiteDatabase.OPEN_READWRITE);
} catch (SQLiteException ex) {
Conexiones.escribirLog(Log.getStackTraceString(ex),
ctx.getString(R.string.versionReal));
db.close();
}
}
and my way to implement a conexion to database:
public static synchronized ControladorBBDD getBBDD(Context ctx_p)
throws Exception {
if (instancia == null) {
instancia = new ControladorBBDD(ctx_p);
}
return instancia;
}
and to call it from activities:
dblectura = ControladorBBDD.getBBDD(getApplicationContext());
where private ControladorBBDD dblectura;
i hope that it helps, important thing is that you use applicationContext, no Activity context ;))

well if i were u i would create a class and the dbhelper as a subclass then i would use a open and a close function for main class and also the insert
whenever i want to use database i do it like this
mainclass mc=new mainclass(this);
mc.open();
mc.insert();
mc.close();

Android databases are too big to be created on onCreate

On my app I make use of two datatabases.
This is the class that handles the database management and all the query that are made to it.
public class Database {
private DbHelper DBHelper;
private final Context Context;
private SQLiteDatabase MyDBone, MyDBtwo;
static Context ctx;
private static class DbHelper extends SQLiteOpenHelper {
public DbHelper(Context context, String dbName, int dbVersion) {
super(context, dbName, null, dbVersion);
}
#Override
public void onCreate(SQLiteDatabase db) {
// This is where the two databases are created
}
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVesion) {
// database upgrades are handled here
}
}
}
// database constructor
public Database(Context c) {
Context = c;
ctx = c;
}
// database open
public Database open() throws SQLException {
DBHelper = new DbHelper(Context, BD_NAME, BD_VERSION);
// I have here some if code to decide witch one of the bellow is used
if{
MyDBone = DBHelper.getWritableDatabase();
} else{
MyDBtwo = DBHelper.getWritableDatabase();
}
return this;
}
// database close
public void close() {
DBHelper.close();
}
public Cursor getData(........) {
// My querys are made here
}
}
My problem is that the databases are too big. In the onCreate method I'm getting the error: The code of method onCreate(SQLiteDatabase) is exceeding the 65535bytes limit. On the other side, my app is getting very big on size.
I would like to know what's the best way to address this issue since I can't change my databases.
Since my app must be run offline I can't make query's on a webserver.
I beleive that the best aproach would be to, on the first run of the app, download the databases from somewhere on the internet (drive, dropbox or other side) but since my programming skils are a little green I must pospone this to a must do in the future.
Is it possible, maintaining my Database class, prepack the apk with the databases and install them on the sdcard? On the other side this will increase the apk size (the total of the databases is 15 mb).
Please advise on the best way to address this issue.
Regards,
favolas

In Android, this the correct way to setup SQLiteDatabase helpers?

Exception:
CREATE TABLE android_metadata failed
Failed to setLocale() when constructing, closing the database
android.database.sqlite.SQLiteException: database is locked
My app works fine and has no db issues, except when onUpgrade() is called.
When onUpgrade is automatically called, it tries to use the CarManager class below to do data manipulation required for the upgrade. This fails because the db is locked.
Because this seems like it should be a normal thing to do, it seems that I must not be structuring the following code correctly (two classes follow, a helper and a table manager):
public class DbHelper extends SQLiteOpenHelper {
private Context context;
//Required constructor
public DbAdapter(Context context)
{
super(context, "my_db_name", null, NEWER_DB_VERSION);
this.context = context;
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion)
{
overrideDB = db;
CarManager.migrateDataForOnUpgrade(context);
}
}
public class CarManager {
DbHelper dbHelper;
public CarManager(Context context)
{
dbHelper = new DbHelper(context);
}
public void addCar(String make, String model)
{
ContentValues contentValues = new ContentValues();
contentValues.put("make", make);
contentValues.put("model", model);
SQLiteDatabase db = dbHelper.getWritableDatabase();
db.insert("car", null, contentValues);
db.close();
}
public static void migrateDataForOnUpgrade()
{
//Code here that migrates data when onUpgrade() is called
//Db lock happens here
}
}
Any ideas?
Do people set up table manager (ex: dao) differently than this?
edit: I talked to the google team # android developer hours, and they said onUpgrade3 was never meant to do anything like structural changes (alters). So yes, it seems like there are some hacks that must be used in many instances right now.

I use the following model by extending the Application class. I maintain a single static instance of my db helper which all other app components use...
public class MyApp extends Application {
protected static MyAppHelper appHelper = null;
protected static MyDbHelper dbHelper = null;
#Override
protected void onCreate() {
super.onCreate();
...
appHelper = new MyAppHelper(this);
dbHelper = MyAppHelper.createDbHelper();
dbHelper.getReadableDatabase(); // Trigger creation or upgrading of the database
...
}
}
From then on any class which needs to use the db helper simply does the following...
if (MyApp.dbHelper == null)
MyApp.appHelper.createDbHelper(...);
// Code here to use MyApp.dbHelper