CREATING A SELF-REFERENCING URL THAT PRESERVES STATE INFORMATION: 

    $myself = $query->self_url;
    print "<A HREF=$myself>I'm talking to myself.</A>";

self_url will return a URL, that, when selected, will reinvoke this script with all its state information intact. This is most useful when you want to jump around within the document using internal anchors but you don't want to disrupt the current contents of the form. Something like this will do the trick. 

     $myself = $query->self_url;
     print "<A HREF=$myself#table1>See table 1</A>";
     print "<A HREF=$myself#table2>See table 2</A>";
     print "<A HREF=$myself#yourself>See for yourself</A>";

If you don't want to get the whole query string, call the method url to return just the URL for the script: 

    $myself = $query->url;
    print "<A HREF=$myself>No query string in this baby!</A>\n";

You can also retrieve the unprocessed query string with query_string: 

    $the_string = $query->query_string;