string sqlfdate = "\'" + DateTime.Parse(txtfdate.Text.Trim()).ToString("yyyy-MM-dd") + "\'";
string sqltdate = "\'" + DateTime.Parse(txttdate.Text.Trim()).ToString("yyyy-MM-dd") + "\'";
s = "select * from mstbt where feeddate between " + sqlfdate + " and " + sqltdate + " order by 1 desc,2 desc,3 asc";
/gustav