How to store a file in database

protected void save_Click(object sender, EventArgs e)
    {

        if (!string.IsNullOrEmpty(Request.QueryString["ID"]))
        {

            int ID = Convert.ToInt32(Request.QueryString["ID"]);
            if (FileUpload1.HasFile)
            {
                string FileExtension = System.IO.Path.GetExtension(FileUpload1.FileName);
                if (FileExtension.ToLower() != ".doc" && FileExtension.ToLower() != ".docx" && FileExtension.ToLower() != ".pdf")
                {
                    Label1.Text = "Only .doc or .docx or .pdf Files are allowed";
                }
                else
                {
                    string filename = Path.GetFileName(FileUpload1.PostedFile.FileName);
                    string contentType = FileUpload1.PostedFile.ContentType;
                    using (Stream fs = FileUpload1.PostedFile.InputStream)
                    {
                        using (BinaryReader br = new BinaryReader(fs))
                        {
                            byte[] bytes = br.ReadBytes((Int32)fs.Length);

                        }

                    }


                }


                if (IITBAL.Assignments.UpdateFacultyAssignment(ID, SessionId.ToString(), Semester.SelectedItem.Value.ToString(), Course_Name.SelectedItem.Value.ToString(), FileUpload1.FileName.ToString(), date.Text.ToString()))
                {
                    Response.Redirect("Faculty Manage Assignments.aspx");
                }
                else
                {
                    Label1.Text = "Unable to Add Assignment";
                }
            }
        }
        else
        {


            if (FileUpload1.HasFile)
            {
                string FileExtension = System.IO.Path.GetExtension(FileUpload1.FileName);
                if (FileExtension.ToLower() != ".doc" && FileExtension.ToLower() != ".docx" && FileExtension.ToLower() != ".pdf")
                {
                    Label1.Text = "Only .doc or .docx or .pdf Files are allowed";
                }

                else
                {
                    string filename = Path.GetFileName(FileUpload1.PostedFile.FileName);
                    string contentType = FileUpload1.PostedFile.ContentType;
                    using (Stream fs = FileUpload1.PostedFile.InputStream)
                    {
                        using (BinaryReader br = new BinaryReader(fs))
                        {
                            byte[] bytes = br.ReadBytes((Int32)fs.Length);

                        }

                    }

                }


                if (IITBAL.Assignments.AddFacultyNewAssignment(SessionId.ToString(), 
Semester.SelectedItem.Value.ToString(), Course_Name.SelectedItem.Value.ToString(),UploadFile.FileName.ToString(), date.Text.ToString()))
         // IITBAL.Assignment.AddFacultyNewAssignment  mrthod is described below
                {
                    Response.Redirect("Faculty Manage Assignments.aspx");

                }
                else
                {
                    Label1.Text = "Unable to add Assignment";
                }

            }
        }
    }

public static bool AddFacultyNewAssignment(string SessionId, string Semester, string CourseName, string file,string date)
      {
          // query when faculty add new assignment
          string qtext = string.Format("INSERT INTO TblFacultyAssignment(FacultyId,Semester,CourseName,SelectedFile,Date) VALUES ('{0}','{1}','{2}','{3}','{4}')", SessionId, Semester, CourseName, file,date);
          return IITDAL.DAL.ExecuteQuerysql(qtext) > 0;
      }