private int deleteInternal(Uri url, String userWhere, String[] whereArgs) {
        StringBuilder whereClause = getWhereClause(userWhere);
        int match = mUrlMatcher.match(url);
        String idColumnName = null;
        final SQLiteDatabase db = mOpenHelper.getWritableDatabase();
        int count = 0;

        UrlMatch urlMatch = new UrlMatch(url, whereClause, match, db).invoke();
        idColumnName = urlMatch.getIdColumnName();

        idColumnName = setIdColumnNameIfNull(idColumnName);

        appendIfChangedItemIdIsNotNull(idColumnName, urlMatch.getChangedItemId(), whereClause);

        if (DBG) log("delete from " + url + " WHERE  " + whereClause);

        count = db.delete(urlMatch.getTableToChange(), whereClause.toString(), whereArgs);
        count += deleteRecordsFromAdditionTableToChange(whereArgs, urlMatch.getAdditionalTableToChange(), whereClause, db);

        if (urlMatch.isContactDeleted() && count > 0) {
            // since the contact cleanup triggers no longer work for cross database tables,
            // we have to do it by hand here.
            performContactRemovalCleanup(urlMatch.getDeletedContactId());
        }

        notifyOfDeletedRows(urlMatch, match, count);

        return count;
    }

    private int deleteRecordsFromAdditionTableToChange(String[] whereArgs, String additionalTableToChange, StringBuilder whereClause, SQLiteDatabase db) {
        int result = 0;
        if (additionalTableToChange != null){
            result = db.delete(additionalTableToChange, whereClause.toString(), whereArgs);
        }
        return result;
    }