Fix DB_UPDATE_VERSION constant

src/Database/Database.php

@@ -57,6 +57,11 @@ class Database
 		$this->connect();
 
 		DBA::init($this);
+
+		if ($this->isConnected()) {
+			// Loads DB_UPDATE_VERSION constant
+			DBStructure::definition($configCache->get('system', 'basepath'), false);
+		}
 	}
 
 	private function readServerVariables(array $server)