This comment applies specifically to the tools "Spatial Join" and "Dissolve"
in the toolbox of ArcGIS desktop. (I am running 10.3.1)
The interface to these tools allows one to aggregate fields (eg. take sum or mean or median or...) when multiple
feature classes are dissolved or when multiple target feature classes
match the criteria for a spatial join to a target class.
Sound good? Well, no, not really; not as implemented.
For each field that you wish to aggregate
you have to specify how you wish to aggregate it,
or whether to ignore it in the dissolve/join.
I have some Business Analyst (BA) datasets. I want to dissolve
the data by combining multiple census tracts into
a larger geographic area of my own definition.
The BA dataset has about 3000 fields.
Many of these are things like population counts
in various age ranges (hundreds of fields, if not thousands)
That means that I have to point and click myself
through 3000 fields specifying for each whether
I wish to ignore it or how to aggregate it.
Are you going to pay my carpal tunnel treatment bills?
Either my understanding of the python interface
is at fault, or that interface is totally unusable.
(Aside: And BTW why isn't there a tool to join
a target dataset to various source datasets
on a common field, but to aggregate the
data when there are many source records
matching the target record).
Would anyone from ESRI like to comment?