How To Know If A Record Is Empty Or Not, Without Using QueryString?

Hi,
I wrote two queries to search in three tables mp_parent, mp_page and mp_parent
The first one is: 
SELECT mp_page.PID, mp_page.PageID, mp_page.PageContent, mp_page.ParID, mp_page.ChiID,  mp_parent.ParentName FROM mp_page INNER JOIN mp_parent ON mp_page.ParID = mp_parent.ParentID
The second one is:
SELECT mp_page.PID, mp_page.PageID, mp_page.PageContent, mp_page.ParID, mp_page.ChiID, mp_child.ChildName FROM mp_page INNER JOIN mp_child ON mp_page.ChiID = mp_child.ChildID
 
I used this way to display the records in a FormView
    public HttpContext context = HttpContext.Current;
    public void Page_Load(object sender, EventArgs e)
    {
        if (!Page.IsPostBack)
        {
            ViewState["srch"] = context.Items["srch"];
        }
        FormView1.DataSource = GetTable();
        FormView1.DataBind();
    }
 
    private DataTable GetTable()
    {
        SqlConnection SqlCon = new SqlConnection("Data Source=AJ-166DCCD87;Initial Catalog=mp;Integrated Security=True;Pooling=False");
        String SQL1 = "select mp_page.PID, mp_page.PageID, mp_page.PageContent, mp_page.ParID, mp_page.ChiID, mp_parent.ParentID, mp_parent.ParentName from  mp_page INNER JOIN mp_parent ON mp_page.ParID = mp_parent.ParentID where PageContent like '%" + Convert.ToString(ViewState["srch"]) + "%'";
        SqlDataAdapter Adptr = new SqlDataAdapter(SQL1, SqlCon);
        SqlCommandBuilder CB = new SqlCommandBuilder(Adptr);
        DataTable Dt = new DataTable();
        Adptr.Fill(Dt);
        return Dt;
        SqlCon.Close();
    }
 the question is how can I check if one record is empty to witch to another query ??
Is it possible to know without using QueryString?
Thank you