Dear Experts

How to apply primary key on sno column in the following dataset

dim sql = "select * from employees"
        Dim da As new SqlClient.SqlDataAdapter (sql,con)
        'ds.Clear()
        da.Fill(ds, "employees")
        TextBox1.DataBindings.Add("text", ds.Tables("employees"), "sno")
        TextBox2.DataBindings.Add("text", ds.Tables("employees"), "Name")
        TextBox3.DataBindings.Add("text", ds.Tables("employees"), "City")
        TextBox4.DataBindings.Add("text", ds.Tables("employees"), "Phone")

Please help

PrimaryKey property of DataTable.

ds.Tables("tableName").PrimaryKey=new DataColumn(){ ds.Tables("tableName").Columns("fieldName")}