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Hi guys -

 

 

I am still having an issue with my Dynamic Schema workbench working correctly with polygons.  I have finally worked out it is not the workbench itself that has the problem, but my custom-built transformer.

 

 

The transformer is a reprojection transformer and when dealing with polygons it actually GeometryCoercer's the polygons into lines to do the projection, then converts them back to polygons.  I believe that this is why when I run my Dynamic Schema workbench on a shapefile polygon, it comes up with the "Features with no schema defined" error. 

 

 

My question is - is there a way to get the Dynamic Schema function to work, without altering the transformer??  How do I get FME to remember the schema of the polygons before they went through the transformer??

 

 

Thankyou
Hi,

 

 

I am not sure about it since I dont know the exact working of your ws, but you can try to add a readear as a ws resource and use it to define the schema.

 

Itay
Hi,

 

 

I cannot reproduce such a situation. My test workspace works fine for all of point, polyline, polygon features.

 

One possible reason for the error is that fme_featrure_type has been changed. Does your workspace change fme_feature_type only when the feature is polygon?

 

Takashi
Normally this works with all geometry types, so somewhere in your costum transformer, the 'link' is lost with the original schema (as Takashi suggests).
Ok thanks for your replies.  I guess I have to try and repair the link!  But one thing that has me very confused right now is the exact meanings and differences of the following terms:

 

 

fme_feature_type

 

fme_geometry

 

fme_type

 

Schema

 

 

I don't understand the differences between them....

 

 

Thanks,
Oh and in regards to FME_Feature_Type - I noticed that when I ran the workspace Statically rather than Dynamically, and added a text attribute to my writer that linked to the fme_feature_type attribute, the output file for a polygon shapefile had the field empty, but in the output file for a polyline shapefile, fme_feature_type was populated.

 

 

I am assuming this means that I am losing fme_feature_type in the custom transformer for polygons.  Is there a way to keep the link in a dynamic workspace without editing the transformer?  I've tried adding a "Reader as Resource" but this doesn't seem to work....
Hi,

 

 

fme_feature_type will be usually kept unless it is changed or removed explicitely.

 

At first, you should find where fme_feature_type is lost. Then consider how to keep it. The Logger or / and the Inspector help you to specify the location in which fme_feature_type is lost.

 

If the location in the custom transformer, you will have to edit it.   See these links about several related terms: http://docs.safe.com/fme/html/FME_Transformers/Default.htm#geometry/fme_geometry.htm http://docs.safe.com/fme/html/FME_Transformers/Default.htm#geometry/fme_type.htm http://docs.safe.com/fme/html/FME_Transformers/Default.htm#geometry/fme_feature_type.htm http://docs.safe.com/fme/html/FME_Workbench/Default.htm#Understanding_Schema.htm   Takashi
Thanks Takashi,

 


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