Question

我试图使用mysql_fetch_row获取计数值，但回显是Array9，当我只想要9时。

            <?php
          $result = mysql_query("SELECT * FROM `product_category` ORDER BY `product_category_name`");
          while($row = mysql_fetch_array($result)) {

              echo '
              <li  class="ui-shadow" data-count-theme="d">
              <a href="' . $row['product_category_ref_page'] . '.php" data-icon="arrow-r" data-iconpos="right">' . $row['product_category_name'] . '</a><span class="ui-li-count">' . 

                $number = mysql_fetch_row(mysql_query("SELECT COUNT(`category_id`) FROM `products_has_product_category` WHERE `category_id`=" . $row['product_category_id'] . ""));
                echo $number[0];

              '</span></li>';
          }

        ?>

非常感谢任何帮助！

Answer 1

我想发布由Michael Berkowski在另一篇文章中提供的解决方案，我希望它能帮助别人！感谢Kickstart指出我正确的方向！

<?php
          $result = mysql_query("
                        SELECT
                        a.product_category_id, a.product_category_name, a.product_category_ref_page,
                        catcount
                        FROM
                        product_category a
                        LEFT JOIN (
                        SELECT category_id, COUNT(*)  AS catcount
                        FROM products_has_product_category 
                        GROUP BY category_id
                        ) subcount ON a.product_category_id = subcount.category_id
                    ");
          while($row = mysql_fetch_array($result)) {

              echo '
              <li  class="ui-shadow" data-count-theme="d">
              <a href="' . $row['product_category_ref_page'] . '.php" data-icon="arrow-r" data-iconpos="right">' . $row['product_category_name'] . '</a><span class="ui-li-count">' . $row['catcount'] . '</span></li>';
          }

        ?>

Answer 2

不需要嵌套查询。可以使用JOIN完成，如下所示： -

    SELECT a.*, COUNT(b.category_id) AS CatCount
    FROM `product_category` a
    LEFT OUTER JOIN `products_has_product_category` b
    ON a.product_category_id = b.category_id
GROUP BY a.id, a.someothercolumn, a.etc

当我只想要值9时，mysql_fetch_row返回Array9

2 个答案: