Women in Technology

Article:		Building a Simple Search Engine with PHP
Subject:		RE: multiple keywords
Date:		2003-12-22 17:59:54
From:		anonymous2
Response to: RE: multiple keywords
Thank you Daniel. I have been looking at your link above, but have no luck in seeing this through. First of all, I still do not understand the FULLTEXT context. And how I would alter the table to incorporate such feature, then bringing it to the Search.php section. I hope you can help me here. Best regards, Sean

Showing messages 1 through 1 of 1.

• RE: multiple keywords
  2004-09-21 10:57:36  cityslicker [View]
  
  
  Hi All,
  
  Thanks for the code - it is great.
  
  Just inform you of my edits and how I used multiple keywords.
  
  1st of all - I put the keyword extraction script in a function.
  
  I would use it to list titles and keywords of pages as well as main body text. I call the function 3 times for words in a title, twice for keywords and once for main body text. This is a way of scoring a page.
  
  E.g. when a search is done on 'business' and a page title has the word 'business' in it will show 3 occurrences (although I dont show occurrences I just use the score to order the list)
  
  2. Multiple keywords.
  
  Basically, I use the explode() function to get an array or keywords and loop through them applying them to the query. I keep the scores for each word and add them together before displaying the list by highest score.
  
  //CODE
  
  /* Get timestamp before executing the query: */
  $start_time = getmicrotime();
  
  $keyword_array = explode(" ", $_GET['keyword']);
  
  $score = array();
  foreach($keyword_array as $keyword)
  {
  
  /* Set $keyword and $results, and use addslashes() to
  * minimize the risk of executing unwanted SQL commands: */
  
  
  /* Execute the query that performs the actual search in the DB: */
  $result = mysql_query(" SELECT p.page_title AS title,
  COUNT(*) AS occurrences
  FROM pages p, word w, occurrence o
  WHERE p.pageID = o.page_id AND
  w.word_id = o.word_id AND
  w.word_word = \"$keyword\"
  GROUP BY p.pageID
  ORDER BY occurrences DESC
  LIMIT 0, 5" );
  
  
  for( $i = 1; $row = mysql_fetch_array($result); $i++ )
  {
  
  $score[$row['title']] += $row['occurrences']; //Array of scores
  
  }
  }
  
  if(count($score) > 0)
  {
  arsort($score); //Reverse sort the associative array scores by highest
  
  /* Get timestamp when the query is finished: */
  $end_time = getmicrotime();
  
  
  /* Present the search-results: */
  print "<h2>Search results for '".$_GET['keyword']."':</h2>\n";
  //Loop through array and display results
  
  while ($element = each($score)) //Loop through array and output results
  {
  
  echo $element[ "key" ];
  echo " - ";
  echo $element[ "value"];
  echo "
  ";
  
  }
  
  
  /* Present how long it took the execute the query: */
  print "query executed in ".(substr($end_time-$start_time,0,5))." seconds.";
  }
  else
  {
  
  //Display a no pages found page
  
  }
  
  
  // END CODE
  
  This works fine but is a little slower if the user wants to search for a sentence. All in all, it is an easy add-on to the already supplied code that provides multiple keyword searching.
  
  Hope this helps someone!