diff --git a/templates/themes/overboards/theme.php b/templates/themes/overboards/theme.php
index 409062d6..fc1080ad 100644
--- a/templates/themes/overboards/theme.php
+++ b/templates/themes/overboards/theme.php
@@ -74,13 +74,21 @@
 		private function fetchThreads($overboard) {
 			$query   = '';
 			$boards  = listBoards(true);
+			$included_boards = [];
 
 			foreach ($boards as $b) {
 				if (in_array($b, $overboard['exclude']))
 					continue;
+				$included_boards[] = $b;
+			}
+
+			if (empty($included_boards)) {
+				return [];
+			}
+
+			foreach ($included_boards as $b) {
 				// Threads are those posts that have no parent thread
-				$query .= "SELECT *, '$b' AS `board` FROM ``posts_$b`` " .
-					"WHERE `thread` IS NULL UNION ALL ";
+				$query .= "SELECT *, '$b' AS `board` FROM ``posts_$b`` WHERE `thread` IS NULL UNION ALL ";
 			}
 
 			$query  = preg_replace('/UNION ALL $/', 'ORDER BY `bump` DESC', $query);