Making PHP Applications Cache-Friendly - Page 4

by: Klaus A. Brunner

November 16, 2001

Making PHP Applications Cache-Friendly

db/postgresql.php: (virtually identical for other databases)




<?



class query {

 

  var $result;

  var $row;

  var $curr_row;

 

  function query(&amp;$db, $query="") {

  // Constructor of the query object.

  // executes the query, notifies the db object of the query result to clean

  // up later

 

    GLOBAL $modification_file;

 

    if($query!=""){

      if (!empty($this-&gt;result)) {

        $this-&gt;free(); // query not called as constructor therefore there may

                       // be something to clean up.

      }

      $this-&gt;result=@pg_Exec($db-&gt;connect_id, $query);

 

      // catch database-altering SQL statements

      if(isset($modification_file) &amp;&amp; eregi("^(insert|update|alter|delete)", $query))

         touch($modification_file);

 

      $db-&gt;addquery($this-&gt;result);

      $this-&gt;curr_row=0;

    }

  }

?>

Bottom Line

If you have an efficient way of tracking the freshness of your data, implementing proper Last-Modified/If-Modified-Since behaviour for PHP applications is very simple. It has clear benefits for both server and client side, and usually no drawbacks. Considering that, it is surprising how rarely it seems to be used by PHP authors.

Of course, this isn't all there is to creating cache-friendly PHP scripts. For further information, check Mark Nottingham's Caching Tutorial for Web Authors and Webmasters.

--Klaus A. Brunner

« Previous Page

Comment and Contribute

0 Comments (click to add your comment)

Your comment has been submitted and is pending approval.

Author:

Klaus A. Brunner

Comment:

Name/nickname:
Email:

Comment:

(Maximum characters: 1200). You have characters left.