user manual

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Chapter 5
Mapping between Streams
Similar to connecting nodes
, this method of data mapping does not require you to set es sential
fields before hand. With this method, yo u simply connect from o ne stream to another using Map to
from the Data Mapping pop-up menu. This type of data mapping is usefu l for mapping to ter minal
nodes and copying and pa st
ing between s treams. Note: Using the Map to option, you cannot map
to Merge, Append, and all types of source nodes.
Figure 5-47
Mapping a stream from its Sort node to the Type node of another stream
To Map Data between Streams
E Right-click the node that you want to use for connecting to
the new stream.
E On the menu, click:
Data Mapping > Map to
E Use the cursor to select a destination node on the target stream.
E In the dialog box that opens, ensure that fields are properly matched and click OK.
Specifying Essential Fields
When mapping to an existing stream, essential fields will typically be specified by the stream
author. These essential fields indicate whether a particular field is used in downstream operations.
For e xample, th e existing stre am may build a model that uses a field called Churn. In this stream,
Churn is an essential field because y ou could not build the model without it. L ikewise, fie lds use d
in manipulation nodes, such as a Derive n ode, are necessary t o derive the new field. Explicitly
setting such fields as essential helps to ensure that the proper fields in the new source node are
mapped to them. If mandatory fields are not mapped, you will receive an error mess age. If you
decide that certain manipulations or output nodes are unnecessary, you can delete the nodes from
the stream and remove the appropria te fields from the Essentia l Fields list.