public static function GetCount($arFilter = array())
 {
     $DB = App::DB();
     $sql = 'SELECT count(*) FROM ' . self::$table;
     // Фильтр
     if (empty($arFilter)) {
         $where = "";
     } else {
         $where = " WHERE ";
         $where .= filterGlue(filterClear($arFilter));
     }
     $where = str_replace(' GROUP BY ID', '', $where);
     $res = $DB->Query($sql . $where);
     if ($result = $DB->Fetch()) {
         return array_shift($result);
     }
     if ($DB->Error()) {
         dbError($DB->Error());
         return false;
     }
 }
/**
 * Генерация SQL-выражения из массивов
 * @param array $arTables
 * @param string $arOrder
 * @param array $arFilter
 * @param string $arSelect
 * @param array $arLimit
 * @return string
 */
function getListSql($arTables, $arOrder = array(), $arFilter = array(), $arSelect = array(), $arLimit = array())
{
    // Таблицы
    $table = "";
    if (is_array($arTables)) {
        if (!empty($arTables)) {
            $cntTbl = 0;
            foreach ($arTables as $tableAlias => $tableName) {
                $cntTbl++;
                $table .= " `" . $tableName . "` as " . $tableAlias;
                if ($cntTbl < count($arTables)) {
                    $table .= ", ";
                }
            }
        } else {
            return false;
        }
    } else {
        if (!empty($arTables)) {
            $table = $arTables;
        } else {
            return false;
        }
    }
    // Порядок
    if (!$arOrder or empty($arOrder)) {
        $arOrder = array("SORT" => "ASC");
    }
    $order = getOrderSql($arOrder);
    // Выборка
    if (!$arSelect or empty($arSelect)) {
        if (count($arTables) > 1) {
            $select = "DISTINCT *";
        } else {
            $select = "*";
        }
    } elseif ($arSelect = "**") {
        $select = "DISTINCT *";
    } else {
        $select = glueArraySql($arSelect, "S");
    }
    // Фильтр
    if (!$arFilter or empty($arFilter)) {
        $where = "";
    } else {
        $where = "WHERE ";
        $where .= filterGlue($arFilter, $arTables);
    }
    // Лимит
    if (!$arLimit) {
        $limit = "";
    } else {
        $limit = getLimitSql($arLimit);
    }
    $sql = "SELECT " . $select . " FROM " . $table . " " . $where . $order . $limit . ";";
    return $sql;
}