Let's say I have data with an attribute "A" which is an integer. I want to process all incoming features with the same attribute the same way (example: check for overlapping geometries within that group of features). But I do not know beforehand what that number will be. How do I do that in FME? Looking for something like AttributeFilter, but with unknown attributes.
I suspect the "group-by" option can do this for some tools, but I'm not sure how to apply it for this problem.

Here you have some polygons an you don't know the values. The number is the Group-By parameter, the string under is the "text". Important, maybe you must rename the column of one file. Both files must have the same column name to Group-By to the parameter. 
