mysql - 将 MySQL 条目排序为子项和父项

Question

所以我有一个表，列是 id、parent-id 和 name。

这是显示的内容。

1 Web Design
- 5 Templates
- 6 Finished Websites
2 Graphic Design
3 Photography
4 Image Manipulation

来自这里:

while($row = mysql_fetch_array( $result )) {
 echo $row['id'] . " ";
 echo $row['name'] . "<br/ >";

 while($row = mysql_fetch_array( $result2 )) {
  echo "- " . $row['id'] . " ";
  echo $row['name'] . "<br/ >";
 }
}

我如何动态地列出他们各自 parent 下的所有 child ，例如......

1 Web Design
- 5 Templates
- 6 Finished Websites
2 Graphic Design
- 7 T-Shirts
- 8 Logos
3 Photography
- 9 Portraits
- 10 Nature
- 11 Animal
- 12 Architecture
4 Image Manipulation

Answer 1

没关系，明白了....

// Get all the data from the "example" table
$result = mysql_query("SELECT * FROM `portfolio-categories` WHERE `parent-id` ='0'")
or die(mysql_error());

// keeps getting the next row until there are no more to get

$parent = 0; 

while($row = mysql_fetch_array( $result )) {
    echo $row['id'] . " ";
    echo $row['name'];

    $parent += 1;
    echo "#" . $parent . "#";

    echo "<br/ >";

    $result2 = mysql_query("SELECT * FROM `portfolio-categories` WHERE `parent-id`=$parent")
or die(mysql_error());

    while($row = mysql_fetch_array( $result2 )) {
        echo "- " . $row['id'] . " ";
        echo $row['name'] . "<br/ >";
    }
}