Sqlite db is not getting created

Question

I am trying to create an app which uses one time login.When it is opened it checks if the sqlite db is present.If it is present it goes to local login page. If the db is not present it creates a new db. I'm stuck in checking the database part.I tried using this and this. It did not work.

Mainactivity.java

public class MainActivity extends Activity {

boolean exists;
SQLiteDBHelper db;
private static final String DATABASE_PATH = "/data/data/com.example.pos_1/databases";
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.start);
    db=new SQLiteDBHelper(this);
    exists=db.checkDataBase();
    if(exists)
    {
        Toast.makeText(getApplicationContext(),"db present",Toast.LENGTH_LONG).show();
        MainActivity.this.startActivity(new Intent(MainActivity.this, Activity_three.class));
    }
    else
    {

        Toast.makeText(getApplicationContext(),"db absent",Toast.LENGTH_LONG).show();
        MainActivity.this.startActivity(new Intent(MainActivity.this, ActivityTwo.class));
    }
}

SQLiteDBHelper

public class SQLiteDBHelper extends SQLiteOpenHelper{
private static final String DATABASE_NAME = "local";
private static final int DATABASE_VERSION = 1;

private static final String DATABASE_PATH = "/data/data/com.example.pos_1/databases/";
public static final String TABLE_NAME = "users";

Context context;




//modified constructor
public SQLiteDBHelper(Context context) {
    super(context, DATABASE_NAME, null, DATABASE_VERSION);
    this.context = context;

}

/*public class MyClass {

    private Context cont;

   // public MyClass(Context c) {
        //cont = c;
    //}

    public boolean MyClass(Context context) {
        File dbFile = new File(DATABASE_PATH + DATABASE_NAME);
        Toast.makeText(context, "db exists", Toast.LENGTH_LONG).show();
        return dbFile.exists();
    }
}*/

public boolean checkDataBase() {
    /*SQLiteDatabase checkDB = null;
        checkDB = SQLiteDatabase.openDatabase(DATABASE_PATH, null,
                SQLiteDatabase.OPEN_READONLY);
        checkDB.close();

        if(checkDB==null)
        {
            Toast.makeText(this.context,"error",Toast.LENGTH_LONG).show();
            return false;
        }
        else
            return true;
    SQLiteDatabase checkDB = null;

    try{
        String myPath = DATABASE_PATH + DATABASE_NAME;
        checkDB = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);
    }catch(SQLiteException e){

        Toast.makeText(this.context,"error",Toast.LENGTH_LONG).show();
        //database does't exist yet.
    }

    if(checkDB != null){
        Toast.makeText(this.context,"check",Toast.LENGTH_LONG).show();
        checkDB.close();
    }

    return checkDB != null ? true : false;

    Log.v(TAG, "is DB present Entry!!!");
    boolean checkFlag = true;
    SQLiteDatabase testDb;
    String testPath = DATABASE_PATH + DATABASE_NAME;
    try {
        Log.v(TAG, "try block1");
        this.getDatabaseName();
        testDb = SQLiteDatabase.openDatabase(testPath, null,
                SQLiteDatabase.OPEN_READWRITE);
        Log.v(TAG, "try block2");
        if(testDb!=null)
            return  true;
    }
    catch(SQLiteException sqlException){
        Toast.makeText(context,sqlException.getMessage(),Toast.LENGTH_LONG);
        Log.v(TAG, "DB absent");
        checkFlag=false;
    }
    //Log.v(TAG, "is DB present Exit!!!");
    return checkFlag;*/
    try{
        Log.d("opendb","before opening");
        SQLiteDatabase   dbe = SQLiteDatabase.openDatabase("/data/data/com.example.pos_1/databases/local", null,0);
        Log.d("opendb","EXIST");
        dbe.close();
        return true;
    }

    catch (SQLiteException sqlException)
    {
        Log.d("opendb","NOT EXIST");
        return  false;
    }
}
@Override
public void onCreate(SQLiteDatabase sqLiteDatabase) {

    //sqLiteDatabase.execSQL("create table rhbus(USERNAME TEXT PRIMARY KEY,PASSWORD TEXT)");
    executeSQLScript(sqLiteDatabase, "create.sql");

}
private void executeSQLScript(SQLiteDatabase database,String dbname) {
    ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
    byte buf[] = new byte[1024];
    int len;
    AssetManager assetManager = context.getAssets();

    InputStream inputStream = null;

    try{
        inputStream = assetManager.open(dbname);
        while ((len = inputStream.read(buf)) != -1) {
            outputStream.write(buf, 0, len);
        }
        outputStream.close();
        inputStream.close();

        String[] createScript = outputStream.toString().split(";");
        for (int i = 0; i < createScript.length; i++) {
            String sqlStatement = createScript[i].trim();

            if (sqlStatement.length() > 0) {
                database.execSQL(sqlStatement + ";");
            }
        }
    } catch (IOException e){

    } catch (SQLException e) {

    }
}
@Override
public void onUpgrade(SQLiteDatabase sqLiteDatabase, int i, int i1) {
    sqLiteDatabase.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
    onCreate(sqLiteDatabase);
}

if you just want to store the login details just use "SharedPreference" — Pranav Ashok, Mar 16 '18 at 06:29
while working with sqlite database make sure to uninstall the previous app before running the new one — Pranav Ashok, Mar 16 '18 at 06:32
I unistalled it each time before installing it.The result is still the same. — Raksha, Mar 16 '18 at 06:35
For just login details why use sqlite , just go with sharepreferences — Manohar, Mar 16 '18 at 06:47
sqLiteDatabase.execSQL("create table rhbus(USERNAME TEXT PRIMARY KEY,PASSWORD TEXT)"); un-comment and comment executeSQLScript(sqLiteDatabase, "create.sql"); and try to get the table count for checking if the table is created or not — Pranav Ashok, Mar 16 '18 at 06:49
If you want to store login details only then use `SharedPreference`. why you need to create a database to store only 2 data, when It can be handled using `SharedPreference`. — R G, Mar 16 '18 at 07:13
The database should have some tables for that specific user.So the database part is necessary. — Raksha, Mar 16 '18 at 07:20
just use database table version 3 and put a ";" at the end of query like this ("create table rhbus(USERNAME TEXT PRIMARY KEY,PASSWORD TEXT);") — Pranav Ashok, Mar 16 '18 at 07:30

MikeT · Accepted Answer · 2018-03-16T09:46:50.263

I believe that your issue is that as there is never any attempt to open the database and thus that the onCreate method is never invoked.

I'd suggest adding a forced attempt to open the database in the SQLiteDBHelper's constructor. e.g. by using :-

public SQLiteDBHelper(Context context) {
    super(context, DATABASE_NAME, null, DATABASE_VERSION);
    this.context = context;
    this.getWritableDatabase(); //<<<< force invocation of the onCreate method if the database doesn't exist.
}

The following replacement for the executeSQLScript may also assist (logging of SQL statements extracted added)

private void executeSQLScript(SQLiteDatabase database, String dbname) {
    ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
    byte buf[] = new byte[1024];
    int len;
    AssetManager assetManager = context.getAssets();

    InputStream inputStream = null;

    try {
        inputStream = assetManager.open(dbname);
        while ((len = inputStream.read(buf)) != -1) {
            outputStream.write(buf, 0, len);
        }
        outputStream.close();
        inputStream.close();

        String[] createScript = outputStream.toString().split(";");
        for (int i = 0; i < createScript.length; i++) {
            Log.d("DBCreate","Read Line :- " + createScript[i].toString());
            String sqlStatement = createScript[i].trim();


            if (sqlStatement.length() > 0) {
                database.execSQL(sqlStatement + ";");
            }
        }
    } catch (IOException e) {

    } catch (SQLException e) {

    }
}

NOTE!

If failures are encountered the above change will result in the database being created so to fix and rerun would require that the database is deleted (delete Apps data or Uninstall the App)

adding `this.getWritableDatabase()` worked. Thank you – Raksha Mar 16 '18 at 10:10 — Raksha, Mar 16 '18 at 10:10

Sqlite db is not getting created

Mainactivity.java

SQLiteDBHelper

1 Answers1

NOTE!