customize advanced search

I am trying to customize the advanced search page so that values input for the tag field appear as a dropdown menu. I thought I could do this by adding a function to FormFunctions.php and modifying advanced- search.php

This is the function I added to FormFunctions.php:

function select_tag($props = array(), $value=null, $label=null,
$search = array())
return _select_from_table('Tags', $props, $value, $label,

In advanced-search.php, I replaced the existing code

<div class="field">
<?php echo label('tag-search', 'Search By Tags'); ?>
<div class="inputs"><?php echo text(array('name'=>'tags','size' =>

with the following:

<div class="field"
<?php echo label('tag-search', 'Search By Tags'); ?>
<div class="inputs"><?php echo select_tag(array('name'=>'tag',
'id'=>'tag-search'), $_REQUEST['tag']); ?></div>

These changes generated the following error:

Error:Column pairs must be defined in order to use

I don't want to get in further over my head. First, it looks as though I should make a copy of application/views/scripts/items/
advanced-search.php in my theme under the items folder before I do anything else.

Do you have any suggestions?

If this can be accomplished, I would also like to add subject as a dropdown menu option.

Thank you.