如何使用PHP和MySQL按字母顺序和数字方式获取数据？

How can I get data alphabetically letter-wise and numeric-wise using PHP and MySQL?

I want to display my data like this:

**0-9      A             B              C           D               E        **
   1       Apple         Beautiful      Cat         DAD             Ear 
   2       Ant           Ball           Cart        Doll            Eat

Please help me approach this using PHP and MySQL.

<ul>
    <?php include "config.php";
        $sql4 = mysql_query("select * from categories");
        $count = mysql_num_rows($sql4);
        while($rows = mysql_fetch_array($sql4)){
     ?>

<li><?php echo $rows['category_name'] ?></li>
<?php } ?>

</ul>

You could create a 2D array: Let the $result be the mysql_result of your query:

$data = array();
while($row = mysql_fetch_assoc($result)) {
  $letter = strtolower(substr($row["category_name"],0,1));
  if(is_numeric($letter)) $letter = "0-9";
  if(!isset($data[$letter])) $data[$letter] = array();
  $data[$letter][] = $row["category_name"];
}

and then iterate it to produce the table you want:

foreach($data as $column=>$values) {
  // $column contains the first letter (or 0-9)
  foreach($values as $value) {
    // $value contains category_name
  }
}

I hope you can finish it from this point, since this site is not supposed to solve all the problem for you.

update skills to PDO as mysql will not work soon.

    <?php include "config.php";
        $sql4 = mysql_query("select * from categories order by category_name ASC");
        $count = mysql_num_rows($sql4);
        while($rows = mysql_fetch_array($sql4)){

    $l = $row['category_name'][0]; // first letter/number
    $category_list[$l][]= $row['category_name'];
}

you will have to design this bit how ever you want yourself.

<ul>
<?php
if(is_array($category_list)){
foreach($category_list as $k=>$v) {
    echo "<li>$k</li>"; // letter/number

    foreach($v as $cat) {
      echo "<li>$cat</li>"; // category name
  }

  }
}
?>
</ul>