SqlBulkCopy.BatchSize Property

Definition

Namespace:

System.Data.SqlClient

Assembly:

System.Data.SqlClient.dll

Package:

System.Data.SqlClient v4.9.0

Source:

System.Data.SqlClient.notsupported.cs

Number of rows in each batch. At the end of each batch, the rows in the batch are sent to the server.

C#

public int BatchSize { get; set; }

Property Value

Int32

The integer value of the BatchSize property, or zero if no value has been set.

Examples

The following console application demonstrates how to bulk load data in batches of 50 rows. For an example illustrating how BatchSize works with a transaction, see Transaction and Bulk Copy Operations.

In this example, the source data is first read from a SQL Server table to a SqlDataReader instance. 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.

C#

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;";
    }
}

Remarks

A batch is complete when BatchSize rows have been processed or there are no more rows to send to the destination data source.

Zero (the default) indicates that each WriteToServer operation is a single batch.

If the SqlBulkCopy instance has been declared without the UseInternalTransaction option in effect, rows are sent to the server BatchSize rows at a time, but no transaction-related action is taken. If UseInternalTransaction is in effect, each batch of rows is inserted as a separate transaction.

The BatchSize property can be set at any time. If a bulk copy is already in progress, the current batch is sized according to the previous batch size. Subsequent batches use the new size. If the BatchSize is initially zero and changed while a WriteToServer operation is already in progress, that operation loads the data as a single batch. Any subsequent WriteToServer operations on the same SqlBulkCopy instance use the new BatchSize.

Applies to

See also

• Bulk Copy Operations in SQL Server
• ADO.NET Overview