Several people have mentioned "event layers" in reference to "feature layers". As I've poked around in the Esri documentation I haven't found a concise explanation for an "event layer". I suspect this may be an older term that isn't currently in use so I put the question out there to all you experienced GIS geeks ... what is an "event layer" and what is the fundamental difference between an "event layer" and a "feature layer". Thank you in advance and both helpful and correct answers will be flagged!
-Cam
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An "event layer" is the result of geometry being dynamically generated from a tabular source. A "feature layer" points to data whose geometry is already defined in a feature class. For example: you have a non-geometric table of xy coordinates. You use a tool to generate point geometry--features. The resultant layer, which is not yet stored in a geodatabase, is an "event layer." If you export the event layer and store it in a geodatabase as a feature class, viewing it in an mxd will be a "feature layer."
Cam,
in what context are talking (ArcGIS Desktop, Javascript API, Flex...).
Tim
Good clarification question Tim. I was thinking specifically in the context of layers created using ArcGIS Desktop and hosted in ArcGIS Server.
An "event layer" is the result of geometry being dynamically generated from a tabular source. A "feature layer" points to data whose geometry is already defined in a feature class. For example: you have a non-geometric table of xy coordinates. You use a tool to generate point geometry--features. The resultant layer, which is not yet stored in a geodatabase, is an "event layer." If you export the event layer and store it in a geodatabase as a feature class, viewing it in an mxd will be a "feature layer."
Hi all,
In my comprehension, the principal differences between are that the EVENT LAYER is a kind of virtual layer (that's why it dont require an output file/folder name) that stay connected to the table used to create it. When the source table change (editing, adding or removing items), the change is automatically applyed to the event layer. In principle, if it's editable, all edits made on it will be applyed also on the source table.
While a FEATURE LAYER is a stand alone layer, totally indepent from the source table (if create from a source table). It can be used, edited in all way without impacting the source table, and vice versa.
Hope that will help.