diff --git a/phpBB/includes/search/fulltext_postgres.php b/phpBB/includes/search/fulltext_postgres.php
index a9b122931b..7d7b3f6fa8 100644
--- a/phpBB/includes/search/fulltext_postgres.php
+++ b/phpBB/includes/search/fulltext_postgres.php
@@ -656,6 +656,8 @@ class phpbb_search_fulltext_postgres extends phpbb_search_base
 			$field = 'topic_id';
 		}
 
+		$this->db->sql_transaction('begin');
+
 		// Only read one block of posts from the db and then cache it
 		$result = $this->db->sql_query_limit($sql, $this->config['search_block_size'], $start);
 
@@ -668,7 +670,35 @@ class phpbb_search_fulltext_postgres extends phpbb_search_base
 		// retrieve the total result count if needed
 		if (!$result_count)
 		{
-			$result_count = sizeof ($id_ary);
+			if ($type == 'posts')
+			{
+				$sql_count = "SELECT COUNT(*) as result_count
+					FROM " . $sql_sort_table . POSTS_TABLE . ' p' . (($firstpost_only) ? ', ' . TOPICS_TABLE . ' t ' : ' ') . "
+					WHERE $sql_author
+						$sql_topic_id
+						$sql_firstpost
+						$m_approve_fid_sql
+						$sql_fora
+						$sql_sort_join
+						$sql_time";
+			}
+			else
+			{
+				$sql_count = "SELECT COUNT(*) as result_count
+					FROM " . $sql_sort_table . TOPICS_TABLE . ' t, ' . POSTS_TABLE . " p
+					WHERE $sql_author
+						$sql_topic_id
+						$sql_firstpost
+						$m_approve_fid_sql
+						$sql_fora
+						AND t.topic_id = p.topic_id
+						$sql_sort_join
+						$sql_time
+					GROUP BY t.topic_id, $sort_by_sql[$sort_key]";
+			}
+
+			$result = $this->db->sql_query($sql_count);
+			$result_count = (int) $this->db->sql_fetchfield('result_count');
 
 			if (!$result_count)
 			{
@@ -676,6 +706,8 @@ class phpbb_search_fulltext_postgres extends phpbb_search_base
 			}
 		}
 
+		$this->db->sql_transaction('commit');
+
 		if (sizeof($id_ary))
 		{
 			$this->save_ids($search_key, '', $author_ary, $result_count, $id_ary, $start, $sort_dir);