From c2a3aa3d99097752f7f79525aec1e722feb4aa06 Mon Sep 17 00:00:00 2001
From: Qiang Xue <qiang.xue@gmail.com>
Date: Wed, 18 Sep 2013 16:18:47 -0400
Subject: [PATCH] Fixes #885: removed NULLs from filtering by models.

---
 framework/yii/db/ActiveRelation.php | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/framework/yii/db/ActiveRelation.php b/framework/yii/db/ActiveRelation.php
index 0be4feb..f05c56a 100644
--- a/framework/yii/db/ActiveRelation.php
+++ b/framework/yii/db/ActiveRelation.php
@@ -279,7 +279,9 @@ class ActiveRelation extends ActiveQuery
 			// single key
 			$attribute = reset($this->link);
 			foreach ($models as $model) {
-				$values[] = $model[$attribute];
+				if (($value = $model[$attribute]) !== null) {
+					$values[] = $value;
+				}
 			}
 		} else {
 			// composite keys