The tMap component is configured to join the movie data and the director
data.
Once the movie data and the director data are loaded into the Job, you need
to configure the tMap component to join them to
produce the output you expect.
Procedure
-
Double-click tMap to open its Map
Editor view.
-
Drop the movieID column, the
title column, the releaseYear column and the url column from the left side onto each of the output flow
table.
On the input side (left side) of the Map Editor, each of the two tables represents one of the
input flow, the upper one for the main flow and the lower one for the lookup
flow.
On the output side (right side), the two tables
represent the output flows that you named to out1 and reject when you linked tMap to tFileOutputDelimited in Dropping and linking components.
-
On the input side, drop the directorID column from the main flow table to the Expr.key column of the ID row in the lookup flow table.
This way, the join key between the main flow and the lookup
flow is defined.
-
Drop the directorID column
from the main flow table to the reject table
on the output side and drop the Name column
from the lookup flow table to the out1
table.
The configuration in the previous two steps describes how
the columns of the input data are mapped to the columns of the output data
flow.
From the Schema editor view
in the lower part of the editor, you can see the schemas on both sides have
been automatically completed.
-
On the out1 output flow table,
click the
button to
display the editing field for the filter expression.
-
Enter
row1.directorId != null
This allows tMap to output only the movie records in each
of which the directorID
field is not empty. A record with an empty directorID field is filtered out.
-
On the reject output flow
table, click the
button
to open the settings panel.
-
In the Catch Output Reject
row, select true to output the records with
empty directorID fields in the reject flow.
-
Click Apply, then click
OK to validate these changes and accept
the propagation prompted by the pop-up dialog box.
Results
The transformation is now configured to complete the movie data with the
names of their directors and write the movie records that do not contain any
director data into a separate data flow.
