fixed params in Query to allow execution twice

fixes #1545

framework/CHANGELOG.md

@@ -8,6 +8,7 @@ Yii Framework 2 Change Log
 - Bug #1497: Localized view files are not correctly returned (mintao)
 - Bug #1500: Log messages exported to files are not separated by newlines (omnilight, qiangxue)
 - Bug #1509: The SQL for creating Postgres RBAC tables is incorrect (qiangxue)
+- Bug #1545: It was not possible to execute db Query twice, params where missing (cebe)
 - Bug: Fixed `Call to a member function registerAssetFiles() on a non-object` in case of wrong `sourcePath` for an asset bundle (samdark)
 - Bug: Fixed incorrect event name for `yii\jui\Spinner` (samdark)
 - Enh #1293: Replaced Console::showProgress() with a better approach. See Console::startProgress() for details (cebe)

framework/yii/db/ActiveQuery.php

@@ -122,7 +122,6 @@ class ActiveQuery extends Query implements ActiveQueryInterface
 			$db = $modelClass::getDb();
 		}
 
-		$params = $this->params;
 		if ($this->sql === null) {
 			if ($this->from === null) {
 				$tableName = $modelClass::tableName();
@@ -131,8 +130,8 @@ class ActiveQuery extends Query implements ActiveQueryInterface
 				}
 				$this->from = [$tableName];
 			}
-			list ($this->sql, $params) = $db->getQueryBuilder()->build($this);
+			list ($this->sql, $this->params) = $db->getQueryBuilder()->build($this);
 		}
-		return $db->createCommand($this->sql, $params);
+		return $db->createCommand($this->sql, $this->params);
 	}
 }