Data from SQLite database saved in one activity, can't be shown in other activity

In my app, I'm using an activity to add new courses and save them in the SQLite database. But when I try to access the added courses in an other activity to show them in an Spinner, the table seems to empty.

This is my code to save a course (first activity):

SQLiteHelperCourse courseDbHelper = new SQLiteHelperCourse(this);
    SQLiteDatabase dbw = courseDbHelper.getWritableDatabase();
    String courseNameString, yearString, semesterString, creditsString;
    AlertCourseError courseAlert = new AlertCourseError();

    if(v.getId() == R.id.btnSaveCourse)
    {
        if(!etCourseName.getText().toString().matches("") || !etCredits.getText().toString().matches(""))
        {
            courseNameString = etCourseName.getText().toString();
            yearString = yearSpinner.getSelectedItem().toString();
            semesterString = semesterSpinner.getSelectedItem().toString();
            creditsString = etCredits.getText().toString();

            ContentValues values = new ContentValues();
            values.put(CourseEntry.COLUMN_NAME_COURSE_NAME, courseNameString);
            values.put(CourseEntry.COLUMN_NAME_YEAR, yearString);
            values.put(CourseEntry.COLUMN_NAME_SEMESTER, semesterString);
            values.put(CourseEntry.COLUMN_NAME_CREDITS, creditsString);
            dbw.insert(CourseEntry.TABLE_NAME, CourseEntry.COLUMN_NAME_NULLABLE, values);
        }
}

This is the code to show the saved courses in a Spinner (second activity)

SQLiteDatabase dbr = courseDbHelper.getReadableDatabase();
    String[] projection = { CourseEntry.COLUMN_NAME_COURSE_NAME };
    final ArrayList<String> list = new ArrayList<String>();

    Cursor curs = dbr.query(CourseEntry.TABLE_NAME, projection, null, null,
            null, null, null);
    curs.moveToFirst();

    while (curs.moveToNext()) {
        list.add(curs.getString(curs.getColumnIndexOrThrow(CourseEntry.COLUMN_NAME_COURSE_NAME)));
    }

    final StableArrayAdapter adapter = new StableArrayAdapter(this,
            android.R.layout.simple_spinner_item, list);

    courseSpinner.setAdapter(adapter);