Custom search page and search by title, content and tag

Question

Can someone review my code , I need to know better solutions or any bug.

Okey ! , I made a PHP file to get search results by parameters and search by title , content and tag

PHP's head look like:

include('../../../../wp-config.php');
header('Content-type:text/html;charset=utf-8');
$keyword = $_GET['k'];

That I will bring search results by jQuery after.

My main search function to show result from database:

function search($keyword,$mark){
    while($data=mysql_fetch_array($keyword)){
        if($data['post_status']=='publish'){
            echo '<li>#'.$data['ID'].' '.htmlentities($data['post_title']).' ('.$mark.')</li>';
        }
    }
} 

Search by title function : Full keyword (ex : "jack daniels")

$sql_full_keyword       = "SELECT * from wp_posts WHERE post_title LIKE '$keyword%'";
$search_full_keyword    = mysql_query($sql_full_keyword) or die(mysql_error());
search($search_full_keyword,"Full keyword(s) = '$keyword'");

So i split keyword for next steps like :

$keywords_split         = explode(" ",$keyword);

Search by title function : multi keywords (ex : jack + daniels)

for($i=0;$i<count($keywords_split);$i++){
    $sql_split_keyword      = "SELECT * from wp_posts WHERE post_title LIKE '$keywords_split[$i]%'";
    $search_split_keyword   = mysql_query($sql_split_keyword) or die(mysql_error());
    search($search_split_keyword,"Split keyword = '$keywords_split[$i]'");
}

Search by content function : (same above, but search by content)

for($i=0;$i<count($keywords_split);$i++){
    $sql_split_keyword      = "SELECT * from wp_posts WHERE post_content LIKE '$keywords_split[$i]%'";
    $search_split_keyword   = mysql_query($sql_split_keyword) or die(mysql_error());
    search($search_split_keyword,"Split keyword = '$keywords_split[$i]' (Content)");
}

Than close mysql

mysql_close();

Search by tag function : (using normal wordpress query)

    $tags = str_replace(" ","-",$keyword).",".str_replace(" ",",",$keyword);
    query_posts(array('post_type'=>array('one','two','three') ,'tag' => $tags,'posts_per_page'=>-1));

    while (have_posts()):the_post();
    echo '<li>#'.get_the_ID().' '.get_the_title().'</li>';
    endwhile;

Everything work now and I need someone to review my code, tell me better things or tong ...

Full code here : http://snipt.org/zpz0

Thanks

Answer 1

Search in WordPress is complicated matter because:

1. WP doesn't do it very well out of the box
2. People tend to have varied expectations of how precisely search should work
3. Even light (from human perspective) requirements for search tend to translate in complicated and involved code

Building search from scratch is involved (I know because I did exactly that for a while for clients) and you should totally look for search plugins or other compromise (like search as service) first.

To briefly enumerate specific issues with your code:

• custom Ajax endpoints generally should not be used, see AJAX in Plugins
• using raw MySQL function to query almost never used, see wpdb (and especially parts about securing your queries against injections)
• query_posts() should not be used, see When should you use WP_Query vs query_posts() vs get_posts()?