user manual

93
Building Streams
Step 3: Replace the template source node. Using the Data Mapping option on the pop-up menu
for the templa
te source node, click Select Replacement Node, then select the source node for
the replacement data.
Figure 5-45
Selecting a r
eplacement source node
Step 4: Check mapped fields. I n the dialog box that opens, check that the software is mapping fields
properly
from the replacement data source to the stream. Any unmapped essential fields are
display ed in r ed. These fields are used in stream operations and must be replaced with a sim ilar
field in the new data source in order for downstream operations to function properly. For more
informa t
ion, see the topic Examin ing Mapped F ields on p. 95.
After usin g the dialog box to ensure that all essential fields are properly mapped, the old data
source is disconnected and the new data source is conne cted to the stream using a Filter node
called Ma
p. This Filter node directs the actual mapp ing of fields in t he stream. An Unmap Filter
node is also included on the stream canvas. The Unmap Filter node can b e used to reverse field
name mapping by adding it to the stream. It will undo the mapped fields, but note t hat you will
have to e
dit any downstream terminal nodes to r eselect the fields and overlays.
Figure 5-46
New data source successfully mapped to the stream