SqlBulkCopy.BatchSize 属性

参考

定义

命名空间:: System.Data.SqlClient

程序集:: System.Data.SqlClient.dll

程序集:: System.Data.dll

包:: System.Data.SqlClient v4.8.6

重要

一些信息与预发行产品相关，相应产品在发行之前可能会进行重大修改。对于此处提供的信息，Microsoft 不作任何明示或暗示的担保。

每批中的行数。在每批结束时，会将批中的行发送到服务器。

public:
 property int BatchSize { int get(); void set(int value); };

public int BatchSize { get; set; }

member this.BatchSize : int with get, set

Public Property BatchSize As Integer

属性值

Int32

BatchSize 属性的整数值；如果未设置任何值，则为零。

示例

以下控制台应用程序演示如何以 50 行的批处理批量加载数据。有关说明如何使用 BatchSize 事务的示例，请参阅事务和大容量复制操作。

在此示例中，源数据首先从SQL Server表读取到SqlDataReader实例。源数据不必位于 SQL Server;可以使用可读取到或加载到 IDataReader 的任何DataTable数据源。

重要

除非已按批量复制示例设置中所述创建了工作表，否则此示例不会运行。提供此代码是为了演示仅使用 SqlBulkCopy 时的语法。如果源表和目标表位于同一SQL Server实例中，则使用 Transact-SQL INSERT ... SELECT 语句复制数据会更轻松、更快。

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.
            // 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 the BatchSize.
                bulkCopy.BatchSize = 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 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. 
            ' 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 the BatchSize.
                bulkCopy.BatchSize = 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 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

注解

当处理完 BatchSize 行或没有更多行要发送到目标数据源时，即表示批已完成。

零 (默认) 表示每个 WriteToServer 操作都是单个批处理。

SqlBulkCopy如果声明实例时没有UseInternalTransaction有效选项，则行将一次发送到服务器BatchSize行，但不执行与事务相关的操作。如果 UseInternalTransaction 有效，则每批行作为单独的事务插入。

BatchSize可以随时设置属性。如果批量复制已在进行中，则根据以前的批大小调整当前批的大小。后续批处理使用新大小。 BatchSize如果最初为零并在操作正在进行时WriteToServer更改，则该操作将作为单个批处理加载数据。同一SqlBulkCopy实例上的任何后续WriteToServer操作都使用新的 BatchSize。

适用于

SqlBulkCopy.BatchSize 属性

定义

属性值

示例

注解

适用于

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