Forms Data Controls :: How To Show Data In A Gridview

i have a gridview where i want to show data from 3 tables TRANSACTIONS,WATERMARKED_TEXT and WATERMARKED_LOGOS where in TRANSACTIONS i have ids of other two tables as stored as foreign key in TRANSACTIONS....i want to use the foreign keys and retreive images stored in other two tables...

here is the code for the gridview

private void BindGridView()
{
ConnectionStringSettings set = ConfigurationManager.ConnectionStrings["WATERMARKING"];
String cns = set.ConnectionString;
SqlConnection con = new SqlConnection(cns);
con.Open();
string sql = "SELECT WATERMARKED_LOGOS.WATERMARKED_IMAGE As Image1, WATERMARKED_TEXT.WATERMARKED_IMAGE As Image2, TRANSACTIONS.TRANS_ID As TRANS_ID, TRANSACTIONS.WLID As WLID,TRANSACTIONS.TID As TID, TRANSACTIONS.CATEGORY As CATEGORY FROM TRANSACTIONS
INNER JOIN WATERMARKED_LOGOS ON TRANSACTIONS.WLID = WATERMARKED_LOGOS.WLID INNER JOIN WATERMARKED_TEXT ON TRANSACTIONS.TID = WATERMARKED_TEXT.TID where TRANSACTIONS.USERNAME='" + uName + "'";
SqlDataAdapter da = new SqlDataAdapter(sql, cns);
DataTable dt = new DataTable();
da.Fill(dt);
GridView1.DataSource = dt;
GridView1.DataBind();
con.Close();
}

and html code is here

<Columns>
<asp:BoundField DataField="TRANS_ID" HeaderText="TRANS_ID" />
<asp:BoundField DataField="WLID" HeaderText="LOGO_WATERMARK_ID" />
<asp:BoundField DataField="TID" HeaderText="TEXT_WATERMARK_ID" />
<asp:BoundField DataField="CA