SqlBulkCopy.WriteToServer Method (IDataReader)
Copies all rows in the supplied IDataReader to a destination table specified by the DestinationTableName property of the SqlBulkCopy object.
Assembly: System.Data (in System.Data.dll)
Parameters
- reader
-
Type:
System.Data.IDataReader
A IDataReader whose rows will be copied to the destination table.
The copy operation starts at the next available row in the reader. Most of the time, the reader was just returned by ExecuteReader or a similar call, so the next available row is the first row. To process multiple results, call NextResult on the data reader and call WriteToServer again.
Note that using WriteToServer modifies the state of the reader. The method will call Read until it returns false, the operation is aborted, or an error occurs. This means that the data reader will be in a different state, probably at the end of the result set, when the WriteToServer operation is complete.
While the bulk copy operation is in progress, the associated destination SqlConnection is busy serving it, and no other operations can be performed on the connection.
The ColumnMappings collection maps from the data reader columns to the destination database table.
The following console application demonstrates how to bulk load data from a SqlDataReader. The destination table is a table in the AdventureWorks database.
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. |
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 ' Set up the bulk copy 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" 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
Available since 2.0
