Asp.net 2.0 supports database cache dependencies. So changes in the Tables data can be notified and cache can expire. This is a very handy feature.
Here is how we can do this
<@ outputcache duration= "7200" varybyparam="CustomerID" sqldependency="DatabaseName:Customer" %>
this means the cached page expires in 2 hours but also depends on database table. Any changes on the database table data will also invalidate the cache.
Borrowed the following code from this link: Link to Improved Caching in ASP.NET 2.0
<%@ OutputCache SqlDependency="Pubs:Titles" Duration="6000" VaryByParam="none" %>
<html>
<head runat="server">
<title>Output Cache Titles</title>
</head>
<body>
<form id="form1" runat="server"> <%= DateTime.Now %>
<asp:GridView ID="grdTitles" DataSourceID="SqlDataSource1" Runat="Server" />
<asp:SqlDataSource ID="SqlDataSource1" SelectCommand="Select * FROM Titles" ConnectionString="<%$ ConnectionStrings:mySqlServer %>" Runat="Server" />
</form>
</body>
</html>