Question

当我尝试mysql_fetch_row时，创建的数组包含我在每个索引处选择的2个字段。我想问为什么会这样？

<?php
  $categoryid = $_GET['id']; 
  include('connect.php');

  $query = "SELECT
           Categories_SubCategories.IdCategory,Categories_SubCategories.idSub_Category,
           Categories.Name, Sub_Categories.Name from Categories_SubCategories JOIN 
           Categories on Categories.idCategory = Categories_SubCategories.idCategory  
           JOIN Sub_Categories on Categories_SubCategories.idSub_Category =
           Sub_Categories.idSub_Category
           WHERE Categories_SubCategories.IdCategory = $categoryid";

  $result = mysql_query($query);
  $rows = mysql_num_rows($result);

  for($i=0; $i<$rows; $i++){
     $display = mysql_fetch_row($result);
     echo "$display[3]";
  }
?>

Answer 1

将mysql_num_rows替换为mysql_fetch_array或mysql_fetch_assoc

Answer 2

大多数PHP程序员在想要使用while()时都会使用mysql_fetch_array()循环。

看看这个示例代码：

$query = mysql_query("SELECT id,name FROM tbl_members");
if (mysql_num_rows($query)) {
    while ($result = mysql_fetch_array($query)) {
        echo('User #'.$result['id'].' is: '.$result['name'].'<br />');
    }
}

// Output can be something like this:
// User #1 is: John
// User #2 is: Sarah

Php mysql查询数组在每个数组索引中存储2个字段

2 个答案: