我有一个为页面标题创建独特的标题的功能。它检查该 slug 在页面表中是否可用，然后通过相应地添加“-int”来创建唯一的 slug。该函数对于前三个条目运行良好，例如，输入三次“test slug”将创建“test-slug-1”、“test-slug-2”和“test-slug-3”。然后，第四个条目出现错误“致命错误：超出最大执行时间 30 秒”。逻辑应该有问题，谁能帮我看看。代码如下：

function createSlug($title, $table_name, $field_name) {

global $db_connect;

$slug = preg_replace("/-$/","",preg_replace('/[^a-z0-9]+/i', "-", strtolower($title)));

$counter = 1;

do{

  $query = "SELECT * FROM $table_name WHERE  $field_name  = '".$slug."'";
  $result = mysqli_query($db_connect, $query) or die(mysqli_error($db_connect));


  if(mysqli_num_rows($result) > 0){
      $count = strrchr($slug , "-"); 
      $count = str_replace("-", "", $count);
      if($count > 0){

          $length = count($count) + 1;
          $newSlug = str_replace(strrchr($slug , "-"), '',$slug);
          $slug = $newSlug.'-'.$length;

          $count++;

      }else{
          $slug = $slug.'-'.$counter;
      }  

  }

  $counter++; 
  $row = mysqli_fetch_assoc($result);

}while(mysqli_num_rows($result) > 0);

return $slug;

}

只需访问数据库一次，立即获取所有内容，很可能这是最大的瓶颈。

$query = "SELECT * FROM $table_name WHERE  $field_name  LIKE '".$slug."%'";

然后将结果放入数组中（假设$slugs)

//we only bother doing this if there is a conflicting slug already
if(mysqli_num_rows($result) !== 0 && in_array($slug, $slugs)){
    $max = 0;

    //keep incrementing $max until a space is found
    while(in_array( ($slug . '-' . ++$max ), $slugs) );

    //update $slug with the appendage
    $slug .= '-' . $max;
}

我们使用in_array()检查是否是蛞蝓my-slug the LIKE还会返回诸如

my-slug-is-awesome
my-slug-is-awesome-1
my-slug-rules

等会引起问题的in_array()检查确保我们只检查输入的确切段。

为什么我们不直接计算结果并+1？

这是因为，如果您有多个结果，并删除了一些结果，那么您的下一个 slug 很可能会发生冲突。

E.g.

my-slug
my-slug-2
my-slug-3
my-slug-4
my-slug-5

删除 -3 和 -5 留给我们

my-slug
my-slug-2
my-slug-4

所以，这给了我们 3 个结果，下一个插入将是my-slug-4这已经存在了。

我们为什么不直接使用ORDER BY and LIMIT 1?

We can't just do an order by in the query because ^{the lack of} natural sorting would make my-slug-10 rank lower than my-slug-4 as it compares character by character and 4 is higher than 1

E.g.

m = m
y = y
- = -
s = s
l = l
u = u
g = g
- = -
4 > 1 !!!
  < 0 (But the previous number was higher, so from here onwards is not compared)