Incorrect syntax near '=' when trying to download a file from database in Asp.net webforms c#.

I am trying to download a file from database but it is giving an incorrect syntax error on the line - 
using (SqlDataReader sdr = cmd.ExecuteReader()) I have 3coulmns in my database- SaleID & SaleFilename(this coulmn stores files & their names), SaleName(This column Stores the same files in bytes), Can somebody help me by telling where I am making a maistake
Here is by .aspx code:

<asp:TemplateField HeaderText="SaleName" SortExpression="SaleName"> ...