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Beberapa Operasi Salin Massal

Anda dapat melakukan beberapa operasi penyalinan massal menggunakan satu instans kelas SqlBulkCopy. Jika parameter operasi berubah di antara salinan (misalnya, nama tabel tujuan), Anda harus memperbaruinya sebelum panggilan berikutnya ke salah WriteToServer satu metode, seperti yang ditunjukkan dalam contoh berikut. Kecuali diubah secara eksplisit, semua nilai properti tetap sama seperti pada operasi penyalinan massal sebelumnya untuk instans yang spesifik.

Nota

Melakukan beberapa operasi penyalinan massal menggunakan instans SqlBulkCopy yang sama biasanya lebih efisien daripada menggunakan instans terpisah untuk setiap operasi.

Jika Anda melakukan beberapa operasi penyalinan massal menggunakan objek SqlBulkCopy yang sama, tidak ada batasan apakah informasi sumber atau target sama atau berbeda di setiap operasi. Namun, Anda harus memastikan bahwa informasi asosiasi kolom diatur dengan benar setiap kali Anda menulis ke server.

Penting

Sampel ini tidak akan berjalan kecuali Anda telah membuat tabel kerja seperti yang dijelaskan dalam Penyiapan Contoh Salinan Massal. Kode ini disediakan untuk menunjukkan sintaksis hanya untuk menggunakan SqlBulkCopy . Jika tabel sumber dan tujuan terletak di instans SQL Server yang sama, akan lebih mudah dan lebih cepat untuk menggunakan pernyataan INSERT … SELECT Transact-SQL untuk menyalin data.

static void Main()
{
    var connectionString = GetConnectionString();
    // Open a connection to the AdventureWorks database.
    using (SqlConnection connection =
               new(connectionString))
    {
        connection.Open();

        // Empty the destination tables.
        SqlCommand deleteHeader = new(
            "DELETE FROM dbo.BulkCopyDemoOrderHeader;",
            connection);
        deleteHeader.ExecuteNonQuery();
        SqlCommand deleteDetail = new(
            "DELETE FROM dbo.BulkCopyDemoOrderDetail;",
            connection);
        deleteDetail.ExecuteNonQuery();

        // Perform an initial count on the destination
        //  table with matching columns.
        SqlCommand countRowHeader = new(
            "SELECT COUNT(*) FROM dbo.BulkCopyDemoOrderHeader;",
            connection);
        long countStartHeader = Convert.ToInt32(
            countRowHeader.ExecuteScalar());
        Console.WriteLine($"Starting row count for Header table = {countStartHeader}");

        // Perform an initial count on the destination
        // table with different column positions.
        SqlCommand countRowDetail = new(
            "SELECT COUNT(*) FROM dbo.BulkCopyDemoOrderDetail;",
            connection);
        long countStartDetail = Convert.ToInt32(
            countRowDetail.ExecuteScalar());
        Console.WriteLine($"Starting row count for Detail table = {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(
            "SELECT [SalesOrderID], [OrderDate], " +
            "[AccountNumber] FROM [Sales].[SalesOrderHeader] " +
            "WHERE [AccountNumber] = @accountNumber;",
            connection);
        SqlParameter parameterAccount = new()
        {
            ParameterName = "@accountNumber",
            SqlDbType = SqlDbType.NVarChar,
            Direction = ParameterDirection.Input,
            Value = "10-4020-000034"
        };
        headerData.Parameters.Add(parameterAccount);
        SqlDataReader readerHeader = headerData.ExecuteReader();

        // Get the Detail data in a separate connection.
        using (SqlConnection connection2 = new(connectionString))
        {
            connection2.Open();
            SqlCommand sourceDetailData = new(
                "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()
            {
                ParameterName = "@accountNumber",
                SqlDbType = SqlDbType.NVarChar,
                Direction = ParameterDirection.Input,
                Value = "10-4020-000034"
            };
            sourceDetailData.Parameters.Add(accountDetail);
            SqlDataReader readerDetail = sourceDetailData.ExecuteReader();

            // Create the SqlBulkCopy object.
            using (SqlBulkCopy bulkCopy =
                       new(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 = Convert.ToInt32(
                countRowHeader.ExecuteScalar());
            Console.WriteLine($"{countEndHeader - countStartHeader} rows were added to the Header table.");
            long countEndDetail = Convert.ToInt32(
                countRowDetail.ExecuteScalar());
            Console.WriteLine($"{countEndDetail - countStartDetail} rows were added to the Detail table.");
            Console.WriteLine("Press Enter to finish.");
            Console.ReadLine();
        }
    }
}
Imports System.Data.SqlClient

Module Module1
    Sub Main()
        Dim connectionString As String = GetConnectionString()

        ' Open a connection to the AdventureWorks database.
        Using connection As SqlConnection = New SqlConnection(connectionString)
            connection.Open()

            ' Empty the destination tables.
            Dim deleteHeader As New SqlCommand( _
              "DELETE FROM dbo.BulkCopyDemoOrderHeader;", connection)
            deleteHeader.ExecuteNonQuery()
            deleteHeader.Dispose()
            Dim deleteDetail As New SqlCommand( _
              "DELETE FROM dbo.BulkCopyDemoOrderDetail;", connection)
            deleteDetail.ExecuteNonQuery()

            ' Perform an initial count on the destination table
            ' with matching columns.
            Dim countRowHeader As New SqlCommand( _
               "SELECT COUNT(*) FROM dbo.BulkCopyDemoOrderHeader;", _
                connection)
            Dim countStartHeader As Long = 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.
            Dim countRowDetail As New SqlCommand( _
                "SELECT COUNT(*) FROM dbo.BulkCopyDemoOrderDetail;", _
                connection)
            Dim countStartDetail As Long = System.Convert.ToInt32( _
                countRowDetail.ExecuteScalar())
            Console.WriteLine("Starting row count for Detail table = " & _
               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.
            Dim headerData As SqlCommand = New SqlCommand( _
             "SELECT [SalesOrderID], [OrderDate], " & _
             "[AccountNumber] FROM [Sales].[SalesOrderHeader] " & _
             "WHERE [AccountNumber] = @accountNumber;", _
             connection)

            Dim parameterAccount As SqlParameter = New SqlParameter()
            parameterAccount.ParameterName = "@accountNumber"
            parameterAccount.SqlDbType = SqlDbType.NVarChar
            parameterAccount.Direction = ParameterDirection.Input
            parameterAccount.Value = "10-4020-000034"
            headerData.Parameters.Add(parameterAccount)

            Dim readerHeader As SqlDataReader = _
             headerData.ExecuteReader()

            ' Get the Detail data in a separate connection.
            Using connection2 As SqlConnection = New SqlConnection(connectionString)
                connection2.Open()

                Dim sourceDetailData As SqlCommand = 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)

                Dim accountDetail As SqlParameter = New SqlParameter()
                accountDetail.ParameterName = "@accountNumber"
                accountDetail.SqlDbType = SqlDbType.NVarChar
                accountDetail.Direction = ParameterDirection.Input
                accountDetail.Value = "10-4020-000034"
                sourceDetailData.Parameters.Add( _
                 accountDetail)

                Dim readerDetail As SqlDataReader = _
                 sourceDetailData.ExecuteReader()

                ' Create the SqlBulkCopy object.
                Using bulkCopy As SqlBulkCopy = _
                  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 ex As Exception
                        Console.WriteLine(ex.Message)
                    Finally
                        readerHeader.Close()
                    End Try

                    ' 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 ex As Exception
                        Console.WriteLine(ex.Message)
                    Finally
                        readerDetail.Close()
                    End Try
                End Using

                ' Perform a final count on the destination tables
                ' to see how many rows were added.
                Dim countEndHeader As Long = System.Convert.ToInt32( _
                  countRowHeader.ExecuteScalar())
                Console.WriteLine("{0} rows were added to the Header table.", _
                  countEndHeader - countStartHeader)
                Dim countEndDetail As Long = 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()
            End Using
        End Using
    End Sub

    Private Function GetConnectionString() As String
        Throw New NotImplementedException()
    End Function
End Module

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