query for retrieving column name

you can use following queyr to get the list of columns.

select * from information_schema.columns where table_name = 'customer'

its best to take this approach since Information schema views provide an internal, system table-independent view of the SQL Server metadata.

you can read more here
Information shema views[^]

I suppose this will help you:

using System;
using System.Data;
using System.Data.SqlClient;

   class SchemaTable
   {
      static void Main(string[] args)
      {
         string connString = "server=(local)\\SQLEXPRESS;database=MyDatabase;Integrated Security=SSPI";
         string sql = @"select * from employee";
         SqlConnection conn = new SqlConnection(connString);

         try {
            conn.Open();
            SqlCommand cmd = new SqlCommand(sql, conn);
            SqlDataReader reader = cmd.ExecuteReader();

            DataTable schema = reader.GetSchemaTable();

            foreach (DataRow row in schema.Rows)
            { 
               foreach (DataColumn col in schema.Columns){
                  Console.WriteLine(col.ColumnName + " = " + row[col]);
                  Console.WriteLine("Null value allowed: " + col.AllowDBNull);
               }
            }
            reader.Close();
         } catch(Exception e) {
            Console.WriteLine("Error Occurred: " + e);
         } finally {
            conn.Close();
         }
      }  
   }

this[^] would have yielded 33,000,000 results in just 0.18 seconds, and here you have had waited too long.

Anurag

Refer this page for your answer :

Retriving Column name in SQL Query[^]

Use System view user_tab_columns to fetch the required info.

Select column_name, data_type from user_tab_columns where table_name = 'urtablename'