Export (0) Print
Expand All

Selecting Input Columns Programmatically

After you have programmatically connected components, select the columns from upstream components that you will transform or pass through to downstream components. If you do not select input columns for your component, the component does not receive any rows from the data flow task.

Call the GetVirtualInput method to retrieve the list of available columns from an upstream component, then call the SetUsageType method of the design-time component instance to select columns from the virtual input column collection. When you call this method, the component creates a new input column in its input column collection that has the same lineage ID as the corresponding column in the output collection of the upstream component.

Do not select columns by calling the SetUsageType method of the virtual input object directly, because this bypasses the component's ability to reject columns based on inappropriate data types or other properties.

The following code sample demonstrates how to use the design-time instance of a component to select the columns for a component.

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
Integration Services icon (small) Stay Up to Date with Integration Services

For the latest downloads, articles, samples, and videos from Microsoft, as well as selected solutions from the community, visit the Integration Services page on MSDN:


For automatic notification of these updates, subscribe to the RSS feeds available on the page.

Was this page helpful?
(1500 characters remaining)
Thank you for your feedback

Community Additions

ADD
Show:
© 2014 Microsoft