diff --git a/includes/database/mysql/database.inc b/includes/database/mysql/database.inc
index 24b7d28fa..3d6a22499 100644
--- a/includes/database/mysql/database.inc
+++ b/includes/database/mysql/database.inc
@@ -428,9 +428,27 @@ class DatabaseConnection_mysql extends DatabaseConnection {
     }
   }
 
+  /**
+   * Overridden to quote table and database names with backticks.
+   */
   public function query($query, array $args = array(), $options = array()) {
-    $query = preg_replace('/{([^}]+)}/', '`\1`', $query);
-    // This to make Drush work
+    // Match {table} as well as {db.table} and quote both DB and table with
+    // backticks.
+    $query = preg_replace_callback('/{((.*?)\.)?(.*?)}/', function($matches) {
+      $quoted = '';
+
+      // If there is an explicit database, quote it, too.
+      if ($matches[2] !== '') {
+        $quoted .= '`' . $matches[2] . '`.';
+      }
+
+      // Quote the table name.
+      $quoted .= '`' . $matches[3] . '`';
+
+      return $quoted;
+    }, $query);
+
+    // Make Drush work.
     $query = strtr($query, array(
       ' system.' => ' `system`.',
       '`system` system' => '`system` `system`',