tripal/tripal_search_feature/tripal_search_feature.module

<?php

/*************************************************************************
 * tripal_search_feature_init
 */ 
function tripal_search_feature_init(){
	drupal_add_css(drupal_get_path('theme', 'tripal').'/css/tripal_search_feature.css');
	drupal_add_js(drupal_get_path('theme', 'tripal').'/js/tripal_search_feature.js');
}

/*************************************************************************
 * tripal_search_feature_views_api
 */ 
function tripal_search_feature_views_api() {
   return array(
      'api' => 2.0,
   );
}

// A function to rewrite the SQL statement before submitting the query
// Force GROUP BY feature_id and return only one row

function  tripal_search_feature_views_pre_execute(&$view){
	if ($view->name == 'est_search') {

		// AGGREGATORS
		$search = array('SELECT');
		$replace = array('SELECT min(');
		$view->build_info['query'] = str_replace($search, $replace, $view->build_info['query']);
		$view->build_info['count_query']  = str_replace($search, $replace, $view->build_info['count_query']);
		 
		$search = array(',');
		$replace = array(', min(');
		$view->build_info['query'] = str_replace($search, $replace, $view->build_info['query']);
		$view->build_info['count_query']  = str_replace($search, $replace, $view->build_info['count_query']);
		 
		$search = array(' AS ');
		$replace = array(') AS ');
		$view->build_info['query'] = str_replace($search, $replace, $view->build_info['query']);
		$view->build_info['count_query']  = str_replace($search, $replace, $view->build_info['count_query']);

		// GROUP BY
		if (preg_match("'ORDER BY'",  $view->build_info['query'])) {
			$search = array('ORDER BY');
			$replace = array('GROUP BY feature_for_search.feature_id ORDER BY');
			$view->build_info['query'] = str_replace($search, $replace, $view->build_info['query']);
		} else {
			$view->build_info['query']  .= " GROUP BY feature_for_search.feature_id";
		}
		$view->build_info['count_query'] .= " GROUP BY feature_for_search.feature_id";
		 
		//drupal_set_message($view->build_info['query']);
		//drupal_set_message($view->build_info['count_query']);
		 
	}
}