SQLiteDatabse mydatabase = openOrCreateDatabase("your database name",MODE_PRIVATE,null);

openDatabase(String path, SQLiteDatabase.CursorFactory factory, int flags, DatabaseErrorHandler errorHandler)

openDatabase(String path, SQLiteDatabase.CursorFactory factory, int flags)

openOrCreateDatabase(String path, SQLiteDatabase.CursorFactory factory)

openOrCreateDatabase(File file, SQLiteDatabase.CursorFactory factory)

mydatabase.execSQL("CREATE TABLE IF NOT EXISTS TutorialsPoint(Username VARCHAR,Password VARCHAR);");
mydatabase.execSQL("INSERT INTO TutorialsPoint VALUES('admin','admin');");

Cursor resultSet = mydatbase.rawQuery("Select * from TutorialsPoint",null);
resultSet.moveToFirst();
String username = resultSet.getString(1);
String password = resultSet.getString(2);

public class DBHelper extends SQLiteOpenHelper {
   public DBHelper(){
      super(context,DATABASE_NAME,null,1);
   }
   public void onCreate(SQLiteDatabase db) {}
   public void onUpgrade(SQLiteDatabase database, int oldVersion, int newVersion) {}
}

public class MainActivity extends AppCompatActivity {
    Button b1,b2,b3,b4;
    SQLiteDatabase db;
    EditText n,i;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        b1=(Button)findViewById(R.id.button);
        b2=(Button)findViewById(R.id.button3);
        b3=(Button)findViewById(R.id.button4);
        b4=(Button)findViewById(R.id.button5);
        n=(EditText)findViewById(R.id.editText);
        i=(EditText)findViewById(R.id.editText4);
        db = openOrCreateDatabase("emp", Context.MODE_PRIVATE, null);
        db.execSQL("CREATE TABLE IF NOT EXISTS student1(name VARCHAR, rollno number)");
        b1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                db.execSQL("INSERT INTO student1 VALUES('" + n.getText() + "'," + i.getText() + ");");

            }
        });

        b2.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                //Toast.makeText(MainActivity.this, "hey", Toast.LENGTH_SHORT).show();
                db=openOrCreateDatabase("emp",Context.MODE_PRIVATE,null);
                Cursor c=db.rawQuery("SELECT * FROM student1",null);
                if(c.getCount()==0)
                {
                    Toast.makeText(MainActivity.this, "Error no records found", Toast.LENGTH_SHORT).show();
                }
                StringBuffer buffer=new StringBuffer();
                while(c.moveToNext())
                {
                    buffer.append("Name : "+c.getString(0)+"n");
                    buffer.append("RollNo:"+c.getString(1)+"n");
                }

                Toast.makeText(MainActivity.this, buffer, Toast.LENGTH_SHORT).show();

            }
        });

        b3.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                try {
                    db.execSQL("DELETE FROM student1 WHERE name='" + n.getText().toString() +"';");
                }
                catch(Exception e){
                    Toast.makeText(getApplicationContext(),"Crash",Toast.LENGTH_SHORT).show();
                    e.printStackTrace();
                }
            }
        });

        b4.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                db.execSQL("UPDATE student1 SET name='"+n.getText().toString()+"' where name='heyeee'");
            }
        });



                }


            }