Document database transactions. Closes laravel#194.

database.md

@@ -2,6 +2,7 @@
 
 - [Configuration](#configuration)
 - [Running Queries](#running-queries)
+- [Database Transactions](#database-transactions)
 - [Accessing Connections](#accessing-connections)
 
 <a name="configuration"></a>
@@ -49,6 +50,18 @@ You may listen for query events using the `DB::listen` method:
   //
  });
 
+<a name="database-transactions"></a>
+## Database Transactions
+
+To run a set of operations within a database transaction, you may use the `transaction` method:
+
+ DB::transaction(function()
+ {
+  DB::table('users')->update(array('votes' => 1));
+
+  DB::table('posts')->delete();
+ });
+
 <a name="accessing-connections"></a>
 ## Accessing Connections