@Override public int getCount(Filter filter) { String sql = " SELECT count( DISTINCT p0.sheetid ) FROM purchase0_bak p0 " + " JOIN purchase_bak p ON ( p0.sheetid = p.refsheetid ) " + " JOIN cat_order_bak c ON ( c.sheetid = p0.sheetid ) WHERE " + filter.toString(); String temp = SqlUtil.querySQL4SingleColumn(conn, sql).get(0); int rows = 0; if (temp != null) { rows = Integer.parseInt(temp); } return rows; }