1.大批量数据操作
可以利用SqlBulkCopy类快速写入大批量数据，针对SQL Server的优化，可以写入DataRow数据，DataTable,DataReader
WriteToServer（DataTable）写入数据表
WriteToServer（DataRow[]）批次写入数据行
WriteToServer（DataTable ，DataRowState）按行状态写入数据库表
WriteToServer（IDataReader）写入DataReader对象
string connstr = "server=(local);database=northwind;integrated security=true;async=true";
// Fill up a DataSet
DataSet ds = new DataSet();
SqlConnection conn = new SqlConnection(connstr);
SqlDataAdapter dadp = new SqlDataAdapter("select * from customers", conn);
dadp.Fill(ds);
// Copy the Data to SqlServer
SqlBulkCopy bcp = new SqlBulkCopy(connstr);
bcp.DestinationTableName = "customers1";
bcp.WriteToServer(ds.Tables[0]);
2.多个动态的结果集
Multiple Active Result Sets（MARS）
这个只能在SQL Server 2005中使用
可以在一个Command对象上同时打开多个DataReader
string connstr = "server=(local);database=northwind;integrated security=true;async=true";
SqlConnection conn = new SqlConnection(connstr);
conn.Open();
SqlCommand cmd1 = new SqlCommand("select * from customers", conn);
SqlCommand cmd2 = new SqlCommand("select * from orders", conn);
SqlDataReader rdr1 = cmd1.ExecuteReader();
// next statement causes an error prior to SQL Server 2005
SqlDataReader rdr2 = cmd2.ExecuteReader();
// now you can reader from rdr1 and rdr2 at the same time.
