SqlBulkCopyColumnMapping.SourceColumn 屬性
定義
重要
部分資訊涉及發行前產品，在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊，不做任何明確或隱含的瑕疵擔保。
資料來源中正在對應的資料行名稱。
public:
property System::String ^ SourceColumn { System::String ^ get(); void set(System::String ^ value); };public string SourceColumn { get; set; }member this.SourceColumn : string with get, setPublic Property SourceColumn As String屬性值
SourceColumn 屬性的字串值。
範例
下列範例會從 AdventureWorks 範例資料庫中的來源資料表，將資料大量複製到相同資料庫中的目的地資料表。 雖然目的地中的數據行數目符合來源中的數據行數目，但是數據行名稱和序數位置不相符。 SqlBulkCopyColumnMapping 物件可用來建立大量複製的數據行對應。
重要
除非您已如大量複製範例設定中所述建立工作資料表，否則將不會執行此範例。 這個程式碼僅是為了示範使用 SqlBulkCopy 的語法而提供。 如果來源和目的地數據表位於相同的 SQL Server 實例中，使用 Transact-SQL INSERT … SELECT 語句來複製數據會比較簡單且更快速。
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.BulkCopyDemoDifferentColumns;",
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();
// Set up the bulk copy object.
using (SqlBulkCopy bulkCopy =
new SqlBulkCopy(connectionString))
{
bulkCopy.DestinationTableName =
"dbo.BulkCopyDemoDifferentColumns";
// Set up the column mappings source and destination.
SqlBulkCopyColumnMapping mapID = new SqlBulkCopyColumnMapping();
mapID.SourceColumn = "ProductID";
mapID.DestinationColumn = "ProdID";
bulkCopy.ColumnMappings.Add(mapID);
SqlBulkCopyColumnMapping mapName = new SqlBulkCopyColumnMapping();
mapName.SourceColumn = "Name";
mapName.DestinationColumn = "ProdName";
bulkCopy.ColumnMappings.Add(mapName);
SqlBulkCopyColumnMapping mapNumber = new SqlBulkCopyColumnMapping();
mapNumber.SourceColumn = "ProductNumber";
mapNumber.DestinationColumn = "ProdNum";
bulkCopy.ColumnMappings.Add(mapNumber);
// Write from the source to the destination.
try
{
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.BulkCopyDemoDifferentColumns;", _
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 bulkCopy As SqlBulkCopy = New SqlBulkCopy(connectionString)
bulkCopy.DestinationTableName = _
"dbo.BulkCopyDemoDifferentColumns"
' Set up the column mappings source and destination.
Dim mapID As New SqlBulkCopyColumnMapping()
mapID.SourceColumn = "ProductID"
mapID.DestinationColumn = "ProdID"
bulkCopy.ColumnMappings.Add(mapID)
Dim mapName As New SqlBulkCopyColumnMapping()
mapName.SourceColumn = "Name"
mapName.DestinationColumn = "ProdName"
bulkCopy.ColumnMappings.Add(mapName)
Dim mapNumber As New SqlBulkCopyColumnMapping()
mapNumber.SourceColumn = "ProductNumber"
mapNumber.DestinationColumn = "ProdNum"
bulkCopy.ColumnMappings.Add(mapNumber)
' Write from the source to the destination.
Try
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
備註
SourceColumn和 SourceOrdinal 屬性互斥。 最後一個值集優先。
適用於
另請參閱
- 在 SQL Server 中執行大量複製作業
- ADO.NET 概觀 \(部分機器翻譯\)
