motor de búsqueda en el script php

<?php
//This is a working script
//Make sure to go through it and edit database table filelds that you are seraching
//This script assumes you are searching 3 fields
$hostname_logon = "localhost" ;  
$database_logon = "FAQn" ;  
$username_logon = "root" ;  
$password_logon = "" ;  
//open database connection
 $connections = mysql_connect($hostname_logon, $username_logon, $password_logon) or die ( "Unabale to connect to the database" );
 //select database
 mysql_select_db($database_logon) or die ( "Unable to select database!" );
 
//specify how many results to display per page
$limit = 10;
 
// Get the search variable from URL
  $var = @$_GET['q'] ;
//trim whitespace from the stored variable
  $trimmed = trim($var);
//separate key-phrases into keywords
  $trimmed_array = explode(" ",$trimmed);
 
// check for an empty string and display a message.
if ($trimmed == "") {
  $resultmsg =  "<p>Search Error</p><p>Please enter a search...</p>" ;
  }
 
// check for a search parameter
if (!isset($var)){
  $resultmsg =  "<p>Search Error</p><p>We don't seem to have a search parameter! </p>" ;
  }
// Build SQL Query for each keyword entered
foreach ($trimmed_array as $trimm){
     
// EDIT HERE and specify your table and field names for the SQL query
     $query = "SELECT * FROM que WHERE id LIKE \"%$trimm%\" OR cat_name LIKE  \"%$trimm%\" OR que LIKE \" %$trimm%\"  OR datepos LIKE  \"%$trimm%\" ORDER BY field1   DESC" ;
     // Execute the query to  get number of rows that contain search kewords
     $numresults=mysql_query ($query);
     $row_num_links_main =mysql_num_rows ($numresults);
 
     // next determine if 's' has been passed to script, if not use 0.
     // 's' is a variable that gets set as we navigate the search result pages.
     if (empty($s)) {
         $s=0;
     }
 
      // now let's get results.
      $query .= " LIMIT $s,$limit" ;
      $numresults = mysql_query ($query) or die ( "Couldn't execute query" );
      $row= mysql_fetch_array ($numresults);
 
      //store record id of every item that contains the keyword in the array we need to do this to avoid display of duplicate search result.
      do{
 //EDIT HERE and specify your field name that is primary key
          $adid_array[] = $row[ 'fieldid' ];
      }while( $row= mysql_fetch_array($numresults));
 } //end foreach
 
if($row_num_links_main == 0 && $row_set_num == 0){
   $resultmsg = "<p>Search results for:" . $trimmed  ."</p><p>Sorry, your search returned zero results</p>" ;
}
   //delete duplicate record id's from the array. To do this we will use array_unique function
   $tmparr = array_unique($adid_array);
   $i=0;
   foreach ($tmparr as $v) {
       $newarr[$i] = $v;
       $i++;
   }
 
// now you can display the results returned. But first we will display the search form on the top of the page
?>
 
<form action="search.php" method="get" name="search">
  <div align="center">
      <input name="q" type="text" value=" <?php echo $q; ?> " size="15">
      <input name="search" type="submit" value="Search">
  </div>
</form>
 
<?php
// display what the person searched for.
 if( isset ($resultmsg)){
  echo $resultmsg;
  exit();
 }else{
  echo "Search results for: " . $var;
 }
 
foreach($newarr as $value){
 
// EDIT HERE and specify your table and field names for the SQL query
$query_value = "SELECT * FROM qye WHERE fieldid = '$value'";
 $num_value=mysql_query ($query_value);
 $row_linkcat= mysql_fetch_array ($num_value);
 $row_num_links= mysql_num_rows ($num_value);
 
//now let's make the keywods bold. To do that we will use preg_replace function.
//EDIT parts of the lines below that have fields names like $row_linkcat[ 'field1' ]
//This script assumes you are searching only 3 fields. If you are searching more fileds make sure that add appropriate line.
  $titlehigh = preg_replace ( "'($var)'si" , "<b></b>" , $row_linkcat[ 'field1' ] );
  $linkhigh = preg_replace ( "'($var)'si" , "<b></b>" , $row_linkcat[ 'field2' ] );
  $linkdesc = preg_replace ( "'($var)'si" , "<b></b>" , $row_linkcat[ 'field3' ] );
 
foreach($trimmed_array as $trimm){
    if($trimm != 'b' ){
//IF you added more fields to search make sure to add them below as well.
        $titlehigh = preg_replace( "'($trimm)'si" ,  "<b></b>" , $titlehigh);
        $linkhigh = preg_replace( "'($trimm)'si" , "<b></b>" , $linkhigh);
        $linkdesc = preg_replace( "'($trimm)'si" ,  "<b></b>" , $linkdesc);
     }
//end highlight
 
?>
 <p>
<?php echo $titlehigh; ?><br>
<?php echo $linkhigh; ?><br>
<?php echo $linkhigh; ?>
</p>
 
<?php
}   //end foreach $trimmed_array
   if($row_num_links_main > $limit){
   // next we need to do the links to other search result pages
      if ($s>=1) { // do not display previous link if 's' is '0'
        $prevs=($s-$limit);
         echo "<div align='left'><a href='$PHP_SELF?s=$prevs&q=$var&catid=$catid'>Previous " .$limit. "</a></div>";
      }
     // check to see if last page
     $slimit =$s+$limit;
       if (!($slimit >= $row_num_links_main) && $row_num_links_main!=1) {
     // not last page so display next link
          $n=$s+$limit;
           echo "<div align='right'><a href='$PHP_SELF?s=$n&q=$var&catid=$catid'>Next " .$limit. "</a></div>";
        }
    }
}  //end foreach $newarr
?>