Výběr vstupních sloupců programově

Platí pro:SQL Server SSIS Integration Runtime v rámci Azure Data Factory

Poté, co máte programově propojené komponenty, vyberte sloupce z upstream komponent, které transformujete nebo přenesete do dalších komponent. Pokud nevyberete vstupní sloupce pro svou komponentu, komponenta neobdrží žádné řádky z datového tokového úkolu.

Výběr sloupců

Zavolejte GetVirtualInput metodu pro získání seznamu dostupných sloupců z upstream komponenty, poté zavolejte SetUsageType metodu instance komponenty v době návrhu pro výběr sloupců z kolekce virtuálních vstupních sloupců. Když tuto metodu zavoláte, komponenta vytvoří nový vstupní sloupec ve své kolekci vstupních sloupců, který má stejné rodokmenové ID jako odpovídající sloupec ve výstupní kolekci upstream komponenty.

Nevybírejte sloupce přímo voláním SetUsageType metody virtuálního vstupního objektu, protože tím obcházíte schopnost komponenty odmítat sloupce na základě nevhodných datových typů nebo jiných vlastností.

Sample

Následující ukázka kódu ukazuje, jak použít instanci v době návrhu komponenty k výběru sloupců pro komponentu.

using System;  
using Microsoft.SqlServer.Dts.Runtime;  
using Microsoft.SqlServer.Dts.Pipeline;  
using Microsoft.SqlServer.Dts.Pipeline.Wrapper;  
  
namespace Microsoft.SqlServer.Dts.Samples  
{  
  class Program  
  {  
    static void Main(string[] args)  
    {  
      // Create a package and add a Data Flow task.  
      Package package = new Package();  
      Executable e = package.Executables.Add("STOCK:PipelineTask");  
      TaskHost thMainPipe = e as TaskHost;  
      MainPipe dataFlowTask = thMainPipe.InnerObject as MainPipe;  
  
      // Add an OLE DB connection manager to the package.  
      ConnectionManager conMgr = package.Connections.Add("OLEDB");  
      conMgr.ConnectionString = "Provider=SQLOLEDB.1;" +  
        "Data Source=<servername>;Initial Catalog=AdventureWorks;" +  
        "Integrated Security=SSPI;";  
      conMgr.Name = "SSIS Connection Manager for OLE DB";  
      conMgr.Description = "OLE DB connection to the AdventureWorks database.";  
  
      // Create and configure an OLE DB source component.    
      IDTSComponentMetaData100 source =  
        dataFlowTask.ComponentMetaDataCollection.New();  
      source.ComponentClassID = "DTSAdapter.OleDbSource";  
      // Create the design-time instance of the source.  
      CManagedComponentWrapper srcDesignTime = source.Instantiate();  
      // The ProvideComponentProperties method creates a default output.  
      srcDesignTime.ProvideComponentProperties();  
      // Assign the connection manager.  
      source.RuntimeConnectionCollection[0].ConnectionManager =  
        DtsConvert.GetExtendedInterface(conMgr);  
      // Set the custom properties of the source.  
      srcDesignTime.SetComponentProperty("AccessMode", 2);  
      srcDesignTime.SetComponentProperty("SqlCommand",  
        "Select * from Production.Product");  
  
      // Connect to the data source,  
      //  and then update the metadata for the source.  
      srcDesignTime.AcquireConnections(null);  
      srcDesignTime.ReinitializeMetaData();  
      srcDesignTime.ReleaseConnections();  
  
      // Create and configure an OLE DB destination.  
      IDTSComponentMetaData100 destination =  
        dataFlowTask.ComponentMetaDataCollection.New();  
      destination.ComponentClassID = "DTSAdapter.OleDbDestination";  
      // Create the design-time instance of the destination.  
      CManagedComponentWrapper destDesignTime = destination.Instantiate();  
      // The ProvideComponentProperties method creates a default input.  
      destDesignTime.ProvideComponentProperties();  
  
      // Create the path from source to destination.  
      IDTSPath100 path = dataFlowTask.PathCollection.New();  
      path.AttachPathAndPropagateNotifications(source.OutputCollection[0],  
        destination.InputCollection[0]);  
  
      // Get the destination's default input and virtual input.  
      IDTSInput100 input = destination.InputCollection[0];  
      IDTSVirtualInput100 vInput = input.GetVirtualInput();  
  
      // Iterate through the virtual input column collection.  
      foreach (IDTSVirtualInputColumn100 vColumn in vInput.VirtualInputColumnCollection)  
      {  
        // Call the SetUsageType method of the destination  
        //  to add each available virtual input column as an input column.  
        destDesignTime.SetUsageType(  
           input.ID, vInput, vColumn.LineageID, DTSUsageType.UT_READONLY);  
      }  
  
      // Verify that the columns have been added to the input.  
      foreach (IDTSInputColumn100 inputColumn in destination.InputCollection[0].InputColumnCollection)  
        Console.WriteLine(inputColumn.Name);  
      Console.Read();  
  
      // Add other components to the data flow and connect them.  
    }  
  }  
}  
Imports Microsoft.SqlServer.Dts.Runtime  
Imports Microsoft.SqlServer.Dts.Pipeline  
Imports Microsoft.SqlServer.Dts.Pipeline.Wrapper  
  
Module Module1  
  
  Sub Main()  
  
    ' Create a package and add a Data Flow task.  
    Dim package As Microsoft.SqlServer.Dts.Runtime.Package = _  
      New Microsoft.SqlServer.Dts.Runtime.Package()  
    Dim e As Executable = package.Executables.Add("STOCK:PipelineTask")  
    Dim thMainPipe As Microsoft.SqlServer.Dts.Runtime.TaskHost = _  
      CType(e, Microsoft.SqlServer.Dts.Runtime.TaskHost)  
    Dim dataFlowTask As MainPipe = CType(thMainPipe.InnerObject, MainPipe)  
  
    ' Add an OLE DB connection manager to the package.  
    Dim conMgr As ConnectionManager = package.Connections.Add("OLEDB")  
    conMgr.ConnectionString = "Provider=SQLOLEDB.1;" & _  
      "Data Source=<servername>;Initial Catalog=AdventureWorks;" & _  
      "Integrated Security=SSPI;"  
    conMgr.Name = "SSIS Connection Manager for OLE DB"  
    conMgr.Description = "OLE DB connection to the AdventureWorks database."  
  
    ' Create and configure an OLE DB source component.    
    Dim source As IDTSComponentMetaData100 = _  
      dataFlowTask.ComponentMetaDataCollection.New  
    source.ComponentClassID = "DTSAdapter.OleDbSource"  
    ' Create the design-time instance of the source.  
    Dim srcDesignTime As CManagedComponentWrapper = source.Instantiate  
    ' The ProvideComponentProperties method creates a default output.  
    srcDesignTime.ProvideComponentProperties()  
    ' Assign the connection manager.  
    source.RuntimeConnectionCollection(0).ConnectionManager = _  
      DtsConvert.GetExtendedInterface(conMgr)  
    ' Set the custom properties of the source.  
    srcDesignTime.SetComponentProperty("AccessMode", 2)  
    srcDesignTime.SetComponentProperty("SqlCommand", _  
      "Select * from Production.Product")  
  
    ' Connect to the data source,  
    '  and then update the metadata for the source.  
    srcDesignTime.AcquireConnections(Nothing)  
    srcDesignTime.ReinitializeMetaData()  
    srcDesignTime.ReleaseConnections()  
  
    ' Create and configure an OLE DB destination.  
    Dim destination As IDTSComponentMetaData100 = _  
      dataFlowTask.ComponentMetaDataCollection.New  
    destination.ComponentClassID = "DTSAdapter.OleDbDestination"  
    ' Create the design-time instance of the destination.  
    Dim destDesignTime As CManagedComponentWrapper = destination.Instantiate  
    ' The ProvideComponentProperties method creates a default input.  
    destDesignTime.ProvideComponentProperties()  
  
    ' Create the path from source to destination.  
    Dim path As IDTSPath100 = dataFlowTask.PathCollection.New  
    path.AttachPathAndPropagateNotifications(source.OutputCollection(0), _  
      destination.InputCollection(0))  
  
    ' Get the destination's default input and virtual input.  
    Dim input As IDTSInput100 = destination.InputCollection(0)  
    Dim vInput As IDTSVirtualInput100 = input.GetVirtualInput  
  
    ' Iterate through the virtual input column collection.  
    For Each vColumn As IDTSVirtualInputColumn100 In vInput.VirtualInputColumnCollection  
      ' Call the SetUsageType method of the destination  
      '  to add each available virtual input column as an input column.  
      destDesignTime.SetUsageType(input.ID, vInput, vColumn.LineageID, DTSUsageType.UT_READONLY)  
    Next  
  
    ' Verify that the columns have been added to the input.  
    For Each inputColumn As IDTSInputColumn100 In destination.InputCollection(0).InputColumnCollection  
      Console.WriteLine(inputColumn.Name)  
    Next  
    Console.Read()  
  
    ' Add other components to the data flow and connect them.  
  
  End Sub  
  
End Module