1.5

Table Of Contents
reference later on for more information.
Imagine you are a classic rock fan and you want to extract the data from a CSV listing of all the
albums in your collection. Your goal is to extract records that change whenever the artist OR
the release year changes.
Here's what the CSV looks like:
"Artist","Album","Released"
"Beatles","Abbey Road",1969
"Beatles","Yellow Submarine",1969
"Led Zeppelin","Led Zeppelin 1",1969
"Led Zeppelin","Led Zeppelin 2",1969
"Beatles","Let it be",1969
"Rolling Stones","Let it bleed",1969
"Led Zeppelin","Led Zeppelin 3",1970
"Led Zeppelin","Led Zeppelin 4",1971
"Rolling Stones","Sticky Fingers",1971
Note
The first line is just the header with the names of the CSV columns. Obviously, the data is already
sorted per year, per artist, and per album.
Your goal is to examine two values in each CSV record and to act when either changes. The
DataMapper GUI allows you to specify a On Change trigger, but you can only specify a single
field. So for instance, if you were to set the record boundary when the "Released" field
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