Web Forms :: Meta Tag Populated From Database Not Showing On Page Source

I populate mete tag from database according to this thread [URL] ....

In store.aspx page i have this behinde code

protected void Page_Load(object sender, EventArgs e) {
string data = Server.UrlDecode(Request.QueryString["BehCode"]);
SqlCommand _cmd = new SqlCommand("storeInfo", _cn);
_cmd.CommandType = CommandType.StoredProcedure;
_cmd.Parameters.AddWithValue("@BehCode",data);
_cn.Open();

[Code] ....

Here instead of 

stringkeyword = _dr[0].ToString();

I put

string keyword = _dr["Keyword"].ToString();
 
But when i run website and see viewsource it doesn't show any thing in meta tag.