SqlBulkCopyOptions Enumerazione

Definizione

public enum class SqlBulkCopyOptions

[System.Flags]
public enum SqlBulkCopyOptions

[<System.Flags>]
type SqlBulkCopyOptions = 

Public Enum SqlBulkCopyOptions

Ereditarietà

Object

ValueType

Enum

SqlBulkCopyOptions

Attributi

FlagsAttribute

Campi

Esempio

L'applicazione console seguente illustra come eseguire un caricamento bulk che copia il valore nella colonna Identity della tabella di origine nella colonna corrispondente nella tabella di destinazione, anziché generare un nuovo valore per la colonna Identity di ogni riga.

Per vedere come l'opzione modifica il funzionamento del caricamento bulk, eseguire l'esempio con dbo. Tabella BulkCopyDemoMatchingColumns vuota. Tutte le righe vengono caricate dall'origine. Eseguire quindi di nuovo l'esempio senza svuotare la tabella. Viene generata un'eccezione e il codice scrive un messaggio nella finestra della console che informa che le righe non sono state aggiunte a causa di violazioni della chiave primaria.

using System.Data.SqlClient;

class Program
{
    static void Main()
    {
        string connectionString = GetConnectionString();
        // Open a sourceConnection to the AdventureWorks database.
        using (SqlConnection sourceConnection =
                   new SqlConnection(connectionString))
        {
            sourceConnection.Open();

            // Perform an initial count on the destination table.
            SqlCommand commandRowCount = new SqlCommand(
                "SELECT COUNT(*) FROM " +
                "dbo.BulkCopyDemoMatchingColumns;",
                sourceConnection);
            long countStart = System.Convert.ToInt32(
                commandRowCount.ExecuteScalar());
            Console.WriteLine("Starting row count = {0}", countStart);

            // Get data from the source table as a SqlDataReader.
            SqlCommand commandSourceData = new SqlCommand(
                "SELECT ProductID, Name, " +
                "ProductNumber " +
                "FROM Production.Product;", sourceConnection);
            SqlDataReader reader =
                commandSourceData.ExecuteReader();

            // Create the SqlBulkCopy object using a connection string
            // and the KeepIdentity option.
            // In the real world you would not use SqlBulkCopy to move
            // data from one table to the other in the same database.
            using (SqlBulkCopy bulkCopy =
                new SqlBulkCopy(connectionString, SqlBulkCopyOptions.KeepIdentity))
            {
                bulkCopy.DestinationTableName =
                    "dbo.BulkCopyDemoMatchingColumns";

                try
                {
                    // Write from the source to the destination.
                    bulkCopy.WriteToServer(reader);
                }
                catch (Exception ex)
                {
                    Console.WriteLine(ex.Message);
                }
                finally
                {
                    // Close the SqlDataReader. The SqlBulkCopy
                    // object is automatically closed at the end
                    // of the using block.
                    reader.Close();
                }
            }

            // Perform a final count on the destination
            // table to see how many rows were added.
            long countEnd = System.Convert.ToInt32(
                commandRowCount.ExecuteScalar());
            Console.WriteLine("Ending row count = {0}", countEnd);
            Console.WriteLine("{0} rows were added.", countEnd - countStart);
            Console.WriteLine("Press Enter to finish.");
            Console.ReadLine();
        }
    }

    private static string GetConnectionString()
        // To avoid storing the sourceConnection string in your code,
        // you can retrieve it from a configuration file.
    {
        return "Data Source=(local); " +
            " Integrated Security=true;" +
            "Initial Catalog=AdventureWorks;";
    }
}

Imports System.Data.SqlClient

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

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

            ' Perform an initial count on the destination table.
            Dim commandRowCount As New SqlCommand( _
            "SELECT COUNT(*) FROM dbo.BulkCopyDemoMatchingColumns;", _
                sourceConnection)
            Dim countStart As Long = _
               System.Convert.ToInt32(commandRowCount.ExecuteScalar())
            Console.WriteLine("Starting row count = {0}", countStart)

            ' Get data from the source table as a SqlDataReader.
            Dim commandSourceData As SqlCommand = New SqlCommand( _
               "SELECT ProductID, Name, ProductNumber " & _
               "FROM Production.Product;", sourceConnection)
            Dim reader As SqlDataReader = commandSourceData.ExecuteReader

            ' Create the SqlBulkCopy object using a connection string 
            ' and the KeepIdentity option. 
            ' In the real world you would not use SqlBulkCopy to move
            ' data from one table to the other in the same database.
            Using bulkCopy As SqlBulkCopy = _
              New SqlBulkCopy(connectionString, SqlBulkCopyOptions.KeepIdentity)
                bulkCopy.DestinationTableName = "dbo.BulkCopyDemoMatchingColumns"

                Try
                    ' Write from the source to the destination.
                    bulkCopy.WriteToServer(reader)

                Catch ex As Exception
                    Console.WriteLine(ex.Message)

                    Finally
                        ' Close the SqlDataReader. The SqlBulkCopy
                        ' object is automatically closed at the end
                        ' of the Using block.
                        reader.Close()
                End Try
            End Using

            ' Perform a final count on the destination table
            ' to see how many rows were added.
            Dim countEnd As Long = _
                System.Convert.ToInt32(commandRowCount.ExecuteScalar())
            Console.WriteLine("Ending row count = {0}", countEnd)
            Console.WriteLine("{0} rows were added.", countEnd - countStart)

            Console.WriteLine("Press Enter to finish.")
            Console.ReadLine()
        End Using
    End Sub

    Private Function GetConnectionString() As String
        ' To avoid storing the sourceConnection string in your code, 
        ' you can retrieve it from a configuration file. 
        Return "Data Source=(local);" & _
            "Integrated Security=true;" & _
            "Initial Catalog=AdventureWorks;"
    End Function
End Module

Commenti

È possibile usare l'enumerazione quando si costruisce un'istanza SqlBulkCopyOptionsSqlBulkCopy per modificare il comportamento dei WriteToServer metodi per tale istanza.

Si applica a

Vedi anche

• Operazioni di copia bulk in SQL Server
• Panoramica di ADO.NET