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SqlBulkCopy.NotifyAfter Property

Definition

Defines the number of rows to be processed before generating a notification event.

public:
 property int NotifyAfter { int get(); void set(int value); };
public int NotifyAfter { get; set; }
member this.NotifyAfter : int with get, set
Public Property NotifyAfter As Integer

Property Value

The integer value of the NotifyAfter property, or zero if the property has not been set.

Examples

The following console application demonstrates how to bulk load data using a connection that is already open. The NotifyAfter property is set so that the event handler is called after every 50 rows copied to the table.

In this example, the connection is first used to read data from a SQL Server table to a SqlDataReader instance. Then a second connection is opened to bulk copy the data. Note that the source data does not have to be located on SQL Server; you can use any data source that can be read to an IDataReader or loaded to a DataTable.

Important

This sample will not run unless you have created the work tables as described in Bulk Copy Example Setup. This code is provided to demonstrate the syntax for using SqlBulkCopy only. If the source and destination tables are in the same SQL Server instance, it is easier and faster to use a Transact-SQL INSERT ... SELECT statement to copy the data.

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("NotifyAfter Sample");
            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.
            // 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))
            {
                bulkCopy.DestinationTableName =
                    "dbo.BulkCopyDemoMatchingColumns";

                // Set up the event handler to notify after 50 rows.
                bulkCopy.SqlRowsCopied +=
                    new SqlRowsCopiedEventHandler(OnSqlRowsCopied);
                bulkCopy.NotifyAfter = 50;

                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 void OnSqlRowsCopied(
        object sender, SqlRowsCopiedEventArgs e)
    {
        Console.WriteLine("Copied {0} so far...", e.RowsCopied);
    }
    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("NotifyAfter Sample")
            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. 
            ' 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)
                bulkCopy.DestinationTableName = "dbo.BulkCopyDemoMatchingColumns"

                ' Set up the event handler to notify after 50 rows.
                AddHandler bulkCopy.SqlRowsCopied, AddressOf OnSqlRowsCopied
                bulkCopy.DestinationTableName = _
                 "dbo.BulkCopyDemoMatchingColumns"
                bulkCopy.NotifyAfter = 50

                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 Sub OnSqlRowsCopied(ByVal sender As Object, _
        ByVal args As SqlRowsCopiedEventArgs)
        Console.WriteLine("Copied {0} so far...", args.RowsCopied)
    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

Remarks

This property is designed for user interface components that illustrate the progress of a bulk copy operation. It indicates the number of rows to be processed before generating a notification event. The NotifyAfter property can be set at any time, even while a bulk copy operation is underway. Changes made during a bulk copy operation take effect after the next notification. The new setting applies to all subsequent operations on the same instance.

If NotifyAfter is set to a number less than zero, an ArgumentOutOfRangeException is thrown.

Applies to

See also