About Dynamic Workspaces

Dynamic workspaces provide maximum translation flexibility and minimize long-term maintenance of workspaces.

Dynamic means that the workspace is set up very simply, but with maximum flexibility. You can read any source dataset (of the chosen format), and it will be read and written (to the destination format) correctly. The important part is that you can change the source to a different dataset, and it will still work.

Why Create Dynamic Workspaces?

Traditional FME Workspaces are tightly bound to the source and destination schemas. In many cases, this is what you want. However, in certain situations, the workspace needs to be more independent of the schemas.

A dynamic workspace breaks the dependence on the source and destination schema. Common applications for dynamic workspaces are:

• When a relatively simple data transformation can apply to all the data regardless of schema (that is, clipping, coordinate transformation).
• When the source schema is not predictable or well-defined.
• Ad hoc data transformations.
• When the destination format might vary.
• Long-term maintenance of the workspace is required.

While translations are generally very easy to implement using FME Workbench, in the longer term they may require a lot of maintenance to keep up-to-date. If new feature types or attributes are added to the source data, you must also update the workspace. Sometimes you may not even realize that a data owner has changed their data schema.

What can be made Dynamic

There are a number of components that you could make dynamic in an FME workspace:

Schema: Source Feature Types

A workspace that reads any set of feature types from a source dataset.

This is supported by the Merge Filter.

Schema: Destination Feature Types

A workspace that reads any set of feature types from a source dataset, and writes a corresponding set of feature types.

Schema: Attributes

A workspace that reads any set of attributes on the source feature types and writes them out in the same schema.

Format

A workspace that writes to any format, without the need to add multiple writers.

This is supported by the Generic Writer.

Working with Dynamic Schemas

Dynamic schemas are used in conjunction with adding a reader as a resource.

In most cases, you can use the default schema properties of the dynamic writer. However, there are some parameters you can adjust.

To display dynamic schema parameters, open the dynamic writer Feature Type Properties dialog, and click the Browse button beside Schema Definition:

Feature Type Name

Controls the name of the destination feature type that is written.

• Default: Uses either the source schema or the schema reader feature type name.
• Fixed: Uses the name of the feature type in the workspace, or another name that you specify.
• From Attribute: Has the same effect as dataset fanout, with a new feature type for each value of the specified attribute.

Schema definition

Defines how elements in the schema definition of the feature type are named.

• Default: Schema elements are named based on the feature type name, as specified above.
• Named by Attribute: Schema elements are named based on the specified attribute.

Geometry

Defines how the geometry type of the feature class is derived.

• From Schema Definition: Geometry type is derived from the source schema.
• Fixed: Geometry type is forced to the specified value. (Some formats, such as Esri Shape, have a fixed geometry).
• First Feature Defines Geometry Type: The first feature to reach the writer is used to set the geometry type.

Attributes to remove

This option allows you to remove attributes from the feature. Enter the names of any attributes you do not want in the destination feature (for example, OBJECTID, SHAPE_Area, and any others).

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