How to monitor transaction activity between the databases?

Recently I have been through interesting forum post on SQL Server performance website that a user asking how to monitor transaction activity between the databases without using a third party tool. Until SQL 2000 version it is not that easy to get more information on what you want, but with SQL 2005 by using DMV s you could such information that will help you to determine I/O activity by database. So here to go further details to determine I/O usage by Database: --get I/O statistics by database select...(<a href="http://sqlserver-qa.net/blogs/perftune/archive/2008/01/10/3022.aspx">read more</a>)<img src="http://sqlserver-qa.net/aggbug.aspx?PostID=3022" width="1" height="1">