Dataset Fanout

A Dataset Fanout delivers data to the same feature type, but in multiple datasets. Taking the elevation example again, here the output is a different dataset for each elevation value:

This results in a series of DXF datasets, each of which has one elevation’s worth of contours on one layer.

Setting a Dataset Fanout

A Dataset Fanout is defined in the Navigator window in Workbench, just below the Writer’s dataset parameter:

Double-clicking the Fanout Dataset parameter opens a dialog in which to define the folder to write to and the Fanout Expression to use:

The Fanout Expression can - like the Feature Type fanout - be a simple attribute, like so:

In this case, each feature with a different park name will be written to a different GML output dataset (whereas a feature type fanout would write to different layers in the same dataset).

Additionally, the Text Editor can be used to construct a fanout string:

The result of this translation is a series of GML datasets, each with the park ID and name included:

Two things to notice in that result are:

  • The : (colon) character is not supported in the filename (a Windows limitation) - but this time it had to be removed before running the workspace
  • The file extension (.gml) is necessary as part of the fanout string. FME won't add it automatically.

Miss Vector says…
Fanouts are an important part of writing data with FME, so tell me, which of these statements are true?

1. You can have both a Feature Type Fanout and a Dataset Fanout in the same workspace
2. You can use a Feature Type Fanout with a database format, but not a Dataset Fanout
3. A fanout expression can be an attribute, or a constructed string, but not a user parameter
4. A fanout cannot be based on a format attribute such as fme_color

results matching ""

    No results matching ""