[C#] SQL Query to Databable to CSV

SQL-To-DataTable.cs

// Simple example for 
// 1.) Read a sql server query to datatable;
// 2.) Export it to .csv

    class Program
    {
        static void Main(string[] args)
        {
            var connectionString = @"data source=bla bla bla";
            var selectQuery = "select * from my-table;";
            
            var table = ReadTable(connectionString, selectQuery);
            WriteToFile(table, @"C:\temp\outputfile.csv", false, ",");

            Console.WriteLine("Press any key to quit...");
            Console.ReadKey();
        }

        public static DataTable ReadTable(string connectionString, string selectQuery)
        {
            var returnValue = new DataTable();

            var conn = new SqlConnection(connectionString);

            try
            {
                conn.Open();
                var command = new SqlCommand(selectQuery, conn);

                using (var adapter = new SqlDataAdapter(command))
                {
                    adapter.Fill(returnValue);
                }

            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
                throw ex;
            }
            finally
            {
                if (conn.State == ConnectionState.Open)
                    conn.Close();
            }

            return returnValue;
        }

        public static void WriteToFile(DataTable dataSource, string fileOutputPath, bool firstRowIsColumnHeader = false, string seperator = ";")
        {
            var sw = new StreamWriter(fileOutputPath, false);

            int icolcount = dataSource.Columns.Count;

            if (!firstRowIsColumnHeader)
            {
                for (int i = 0; i < icolcount; i++)
                {
                    sw.Write(dataSource.Columns[i]);
                    if (i < icolcount - 1)
                        sw.Write(seperator);
                }

                sw.Write(sw.NewLine);
            }

            foreach (DataRow drow in dataSource.Rows)
            {
                for (int i = 0; i < icolcount; i++)
                {
                    if (!Convert.IsDBNull(drow[i]))
                        sw.Write(drow[i].ToString());
                    if (i < icolcount - 1)
                        sw.Write(seperator);
                }
                sw.Write(sw.NewLine);
            }
            sw.Close();
        }
    }