Querying an Additional Database for Shortcode Values

Hello Everyone,

I am looking to query an additional database with a plugin that will pull out values and assign them to short codes. What I have built is currently working beautifully, but I want to make sure this thing doesn’t blow up in my face. I have added the code below and I was hoping I could get some confirmation that what I have done will continue to work.

$con = mysql_connect("HOST","USERNAME","PASSWORD");

if (!$con){
    die('Could not connect: ' . mysql_error());
}

mysql_select_db("DB_NAME", $con);
mysql_set_charset('utf8',$con);

function regContentGetterv3(){
    $regQ = "SELECT post_content FROM wp_posts WHERE post_title='$_GET[wver]' ORDER BY ID DESC LIMIT 0,1";
    $regQBOOM = mysql_query($regQ);
    $regContent = mysql_result($regQBOOM, 0);
    return $regContent;
}
add_shortcode('regcontentcodev3', 'regContentGetterv3');