Check if column exists and then do selects from table using C#

Question

please can anyone point me in the right direction. I want to check if the column exists, if so do this select else do another select

    select case 
   when exists (
      SELECT *
      FROM Sys.columns c 
      WHERE c.[object_id] = OBJECT_ID('dbo.Municipality') 
         AND c.name = 'AmountTypeLabel'
   )  
   then 1
   else 0
 end

This Checks if column exists and then return a 0 or a 1 but there is no column name so i can't check it in C#

This is what i have tried in C# but as i said before there is no column name

DataTable DT;
        string SQL = "";
        try
        {

            SQL = "select case " +
                  " when exists( " +
                  "  SELECT 1 " +
                  "  FROM Sys.columns c " +
                  " WHERE c.[object_id] = OBJECT_ID('dbo.Municipality')" +
                  "  AND c.name = 'AmountTypeLabel'" +
                  ")" +
                  " then 1 " +
                  " else 0 " +
                  " end ";
            DT = Conn.ExecuteDT(SQL);
        }
        catch (Exception ex)
        {
            throw new Exception("Unable to get Tables", ex);
        }
        return DT;
    }

Answer 1

With existing code you can fetch the value by using the below and use it in another function:

if(DT.Rows[0][0].ToString() == "1")
 //Do Something

OR you could to use SQL Alias in your SQL query like below:

" end AS ColumnExists";

and then you can refer this in your other function. Sample snippet below -

 if(DT.Rows[0]["ColumnExists"].ToString() == "1")
    //Do Something

On a side note if the requirement is to fetch only the 1 or 0 from SQL server then use the ExecuteScalar as mentioned by Matteo1010 in comments.

 var columnExists = cmd.ExecuteScalar();
 if(columnExists.ToString() == "1")
  //Do Something