您可以使用 SqlBulkCopy 類別的單一執行個體，執行多項大量複製作業。 如果作業參數在不同次複製之間有所變更（例如目的地資料表的名稱），您必須先更新這些參數，才能後續再次呼叫任何 WriteToServer 方法，如下列範例所示。 除非明確變更，否則對於指定的執行個體，所有屬性值都會維持與前一次大量複製作業時相同。
注意
比起對每項作業使用個別的執行個體，使用 SqlBulkCopy 的相同執行個體來執行多項大量複製作業通常更有效率。
如果您使用相同的 SqlBulkCopy 物件執行數項大量複製作業，並未限制來源或目標資訊在每項作業中是否相等或不同。 不過，每次寫入伺服器時，您都必須確保資料行關聯資訊已正確設定。
範例
重要事項
除非您已如大量複製範例設定中所述建立工作資料表，否則此範例不會執行。 這個程式碼僅是為了示範使用 SqlBulkCopy 的語法而提供。 如果來源和目的地資料表位於相同的 SQL Server 執行個體，則使用 Transact-SQL INSERT ... SELECT 陳述式來複製資料會更方便且快速。
using Microsoft.Data.SqlClient;
class Program
{
static void Main()
{
string connectionString = GetConnectionString();
// Open a connection to the AdventureWorks database.
using (SqlConnection connection =
new SqlConnection(connectionString))
{
connection.Open();
// Empty the destination tables.
SqlCommand deleteHeader = new SqlCommand(
"DELETE FROM dbo.BulkCopyDemoOrderHeader;",
connection);
deleteHeader.ExecuteNonQuery();
SqlCommand deleteDetail = new SqlCommand(
"DELETE FROM dbo.BulkCopyDemoOrderDetail;",
connection);
deleteDetail.ExecuteNonQuery();
// Perform an initial count on the destination
// table with matching columns.
SqlCommand countRowHeader = new SqlCommand(
"SELECT COUNT(*) FROM dbo.BulkCopyDemoOrderHeader;",
connection);
long countStartHeader = System.Convert.ToInt32(
countRowHeader.ExecuteScalar());
Console.WriteLine(
"Starting row count for Header table = {0}",
countStartHeader);
// Perform an initial count on the destination
// table with different column positions.
SqlCommand countRowDetail = new SqlCommand(
"SELECT COUNT(*) FROM dbo.BulkCopyDemoOrderDetail;",
connection);
long countStartDetail = System.Convert.ToInt32(
countRowDetail.ExecuteScalar());
Console.WriteLine(
"Starting row count for Detail table = {0}",
countStartDetail);
// Get data from the source table as a SqlDataReader.
// The Sales.SalesOrderHeader and Sales.SalesOrderDetail
// tables are quite large and could easily cause a timeout
// if all data from the tables is added to the destination.
// To keep the example simple and quick, a parameter is
// used to select only orders for a particular account
// as the source for the bulk insert.
SqlCommand headerData = new SqlCommand(
"SELECT [SalesOrderID], [OrderDate], " +
"[AccountNumber] FROM [Sales].[SalesOrderHeader] " +
"WHERE [AccountNumber] = @accountNumber;",
connection);
SqlParameter parameterAccount = new SqlParameter();
parameterAccount.ParameterName = "@accountNumber";
parameterAccount.SqlDbType = SqlDbType.NVarChar;
parameterAccount.Direction = ParameterDirection.Input;
parameterAccount.Value = "10-4020-000034";
headerData.Parameters.Add(parameterAccount);
SqlDataReader readerHeader = headerData.ExecuteReader();
// Get the Detail data in a separate connection.
using (SqlConnection connection2 = new SqlConnection(connectionString))
{
connection2.Open();
SqlCommand sourceDetailData = new SqlCommand(
"SELECT [Sales].[SalesOrderDetail].[SalesOrderID], [SalesOrderDetailID], " +
"[OrderQty], [ProductID], [UnitPrice] FROM [Sales].[SalesOrderDetail] " +
"INNER JOIN [Sales].[SalesOrderHeader] ON [Sales].[SalesOrderDetail]." +
"[SalesOrderID] = [Sales].[SalesOrderHeader].[SalesOrderID] " +
"WHERE [AccountNumber] = @accountNumber;", connection2);
SqlParameter accountDetail = new SqlParameter();
accountDetail.ParameterName = "@accountNumber";
accountDetail.SqlDbType = SqlDbType.NVarChar;
accountDetail.Direction = ParameterDirection.Input;
accountDetail.Value = "10-4020-000034";
sourceDetailData.Parameters.Add(accountDetail);
SqlDataReader readerDetail = sourceDetailData.ExecuteReader();
// Create the SqlBulkCopy object.
using (SqlBulkCopy bulkCopy =
new SqlBulkCopy(connectionString))
{
bulkCopy.DestinationTableName =
"dbo.BulkCopyDemoOrderHeader";
// Guarantee that columns are mapped correctly by
// defining the column mappings for the order.
bulkCopy.ColumnMappings.Add("SalesOrderID", "SalesOrderID");
bulkCopy.ColumnMappings.Add("OrderDate", "OrderDate");
bulkCopy.ColumnMappings.Add("AccountNumber", "AccountNumber");
// Write readerHeader to the destination.
try
{
bulkCopy.WriteToServer(readerHeader);
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
finally
{
readerHeader.Close();
}
// Set up the order details destination.
bulkCopy.DestinationTableName = "dbo.BulkCopyDemoOrderDetail";
// Clear the ColumnMappingCollection.
bulkCopy.ColumnMappings.Clear();
// Add order detail column mappings.
bulkCopy.ColumnMappings.Add("SalesOrderID", "SalesOrderID");
bulkCopy.ColumnMappings.Add("SalesOrderDetailID", "SalesOrderDetailID");
bulkCopy.ColumnMappings.Add("OrderQty", "OrderQty");
bulkCopy.ColumnMappings.Add("ProductID", "ProductID");
bulkCopy.ColumnMappings.Add("UnitPrice", "UnitPrice");
// Write readerDetail to the destination.
try
{
bulkCopy.WriteToServer(readerDetail);
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
finally
{
readerDetail.Close();
}
}
// Perform a final count on the destination
// tables to see how many rows were added.
long countEndHeader = System.Convert.ToInt32(
countRowHeader.ExecuteScalar());
Console.WriteLine("{0} rows were added to the Header table.",
countEndHeader - countStartHeader);
long countEndDetail = System.Convert.ToInt32(
countRowDetail.ExecuteScalar());
Console.WriteLine("{0} rows were added to the Detail table.",
countEndDetail - countStartDetail);
Console.WriteLine("Press Enter to finish.");
Console.ReadLine();
}
}
}
private static string GetConnectionString()
// To avoid storing the connection string in your code,
// you can retrieve it from a configuration file.
{
return "Data Source=(local); " +
" Integrated Security=true;" +
"Initial Catalog=AdventureWorks;";
}
}