Data Controls :: Calculate Age From Date Of Birth And Save It In SQL Server Database?

I am saving users information in Sql Server 2005 Database. The problems are:1. If a user selects 1/Jan/1990 then in the Age column of the database automatically 23 should be saved i.e users age, how do I calculate the age and use it in the query? 2. The format of DateofBirth column  is incorrect it should be 1/Jan/1990 inspite of2013-01-01 00:00:00.000.  The data type is Datetime

------------------Design is--------------

<form id="form1" runat="server">    <div>       
FirstName <asp:TextBox ID="TxtFirstName" runat="server"></asp:TextBox>       
<br />    <br />  LastName    <asp:TextBox ID="TxtLastName" runat="server"></asp:TextBox>       
<br />   <br />        Gender   <asp:DropDownList ID="DdlGender" runat="server" Style="top: 105px; left: 80px;   

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