By the end of this chapter you will be able to:

Combine Data Sets (a union) with a Calculate Stream
Record the source for each record in a Stream
Use the internal variable _pipeName

In this exercise you will produce a single list of updates to customers' Cable TV packages. Customers can update their packages both through the Customer Care system and in shops. You will bring all these updates together into a single list.

Reading in data sets from files

Create a new model with Name: Channel Package Check

There are two files containing updates from the two sources (Customer Care, and Shop).
Customer Care updates
A file containing details of customer care updated can be found in the input files, at:
…\inputData\ChannelPackages\CustomerCareUpdates\CustomerCareUpdates.txt
Shop updates
A file containing details of shop updates can be found in the input files, at:
…\inputData\ChannelPackages\ShopUpdates\ShopUpdates.txt

Load file data into PhixFlow

Add a File Collector to your model
Call this: Customer Care Updates
Navigate to the directory …\train\inputData\ChannelPackages\CustomerCareUpdates
Select the file CustomerCareUpdates.txt – and complete the automatic File Collector and Stream configuration
Add another File Collector to your model
Call this: Shop Updates
Navigate to the directory …\inputData\ChannelPackages\ShopUpdates
Select the file ShopUpdates.txt – and complete the automatic File Collector and Stream configuration
Run both Streams and check that data is loaded into each one from the files

Combine data sets

Create a new Stream in your model:
Hover over CustomerCareUpdates and press - Add a new Stream
Call the new Stream Combined Updates
Drag all attributes from CustomerCareUpdates to Combined Updates
Remember to save your model layout
Add a pipe from the other Stream:
- Hover over ShopUpdates and press - Add a new Connector
- Click on Combined Updates to link the pipe to the output Stream
- Give this pipe the Name: in2
To complete configuration of Combined Updates:
- Double-click on Combined Updates to open the configuration form
- To make the union work, you need to update the Expression for each Attribute: you must remove the reference to the input pipe that PhixFlow has automatically added to the start of each Expression, e.g.:
  - Update the expression

in.CustomerRef

to

CustomerRef

Press in the main Stream configuration form
Run Analysis on Combined Updates
Check that you have the correct number of records in this Stream when the Analysis is complete
Check the data set you generated – make sure that every field in every output record has been populated

Record source for each update

You will now update you configuration to record the source for each update, in the set of combined updates. To do this:

Update the name of the pipe from the Stream CustomerCareUpdates:
- Double-click on the pipe to open the configuration details
- Update the Name to: CC
- Press to save your changes
Update the name of the pipe from ShopUpdates to: shop
Double-click the Stream Combined Updates to open the configuration form
- Add a new Attribute with Name: Source
- Set the Expression of Source to:

if (_pipeName == "CC",
 "Customer Care"
 ,
 "Shop"
 )

Make Source the first Attribute in the Stream: drag it to the top of the Attributes list
Press in the main Stream configuration form
Run analysis on Combined Updates
Check the output data set and make sure that the source has been recorded on each record correctly