WordPress Custom Post Type Converter

gistfile1.aw

<?php

/**
 * Usage: post_type_converter( 'tracks', 'venues');
 */
function post_type_converter( $from=null, $to=null, $post_id=null ){

    global $wpdb;

    $query = "SELECT ID, post_type FROM $wpdb->posts WHERE post_type = '{$from}'";
    $result = $wpdb->get_results( $wpdb->prepare( $query ), 'ARRAY_A' );

    if ( empty( $result ) )
        return print "No post type '{$from}'";

    $tmp_post['post_type'] = null;

    foreach( $result as $r ){

        $tmp_post['ID'] = $r['ID'];
        $tmp_post['post_type'] = $to;

        $id = wp_update_post( $tmp_post);

        if ( $id ) {
            print "Succesfully updated post_id: {$r['ID']} from: {$from} to: {$to}<br />\n";
        } else {
            print "Failed to updat post_id: {$r['ID']} from: {$from} to: {$to}<br />\n";
        }
    }
}