Here is a brief example of my technique...

From a calling page:
--------------------
if ($rsVideoListObj->videolistid > 0) {
    $videoListVideoStruct->videolistid = $rsVideoListObj->videolistid;
    $rsVideoListVideos = getVideoListVideos($videoListVideoStruct);
}

From My UDF:
------------
// get videos for videolist
function getVideoListVideos($inStruct) {
    $queryStr = " SELECT vlj.recordid, vlj.videolistid, vlj.videoid ";
    if( isset($inStruct->getVideoInfo) ) {
        $queryStr .= " , v.videolinkurl, v.showname, v.episodename, v.createdby, v.videocaption, v.videoiconimage ";
        $queryStr .= " , v.regionid, v.urlforsite, v.r2rmediasiteurl, v.googleanalytics ";
    }
    $queryStr .= " FROM videolistvideojoin vlj ";
    if( isset($inStruct->getVideoInfo) ) {
        $queryStr .= " LEFT JOIN videos v ON vlj.videoid = v.videoid";
    }
    
    $queryStr .= " WHERE 0=0 ";
    if( isset($inStruct->videolistid) ) {
        $queryStr .= " AND vlj.videolistid = ".$inStruct->videolistid;
    }
    if( isset($inStruct->videoid) ) {
        $queryStr .= " AND vlj.videoid = ".$inStruct->videoid;
    }
    if( isset($inStruct->orderby) ) {
        $queryStr .= " ORDER BY ".$inStruct->orderby;
    }
    
    $rsData = mysql_query($queryStr);
    if ( mysql_error() && $_SESSION["enabledebug"] ) {
        echo mysql_error();
    }

    $returnVal = $rsData;

    return $returnVal;
}