Combining time fields (temporal table relates)

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06-18-2020 01:57 PM
Status: Open
WernerStangl
New Contributor II

This is somehow related to: Web Map: time slider support for m-1 tabular data related to feature layer 

It happens to me now in the second project in a row that I have entities with geometries that change over time and, independently, with tabular attributes that change over time.

 

An example:

 Province A has a boundary change in 1950 - so there are 2 polygons(A1, A2), one with time fields 1940 and 1950, another one with 1951-1960 . Province A has Governor XYZ from  1932 to 1956 and Governor QWE from 1957 onwards.

So, the "valid" combined chronology would be 1940-1950 (A1,XYZ); 1951-1956 (A2,XYZ); 1957-1960 (A2,QWE).

 

My solution has so far been preprocessing: Do the SQL in a relational database, import it as query table to ArcGIS, query each single year, identify polygons identical between 2 consecutive years using cursor function with arcpy and store "stable time" in two fields and eliminate superfluous polygons.

 

The problem (apart from complexity): It takes forever (it's thousands of entities over hundreds of years), it's rough to reproduce the procedure when the structure or to-be-processed fields change, and there is not just one such related table - in the example: the "province" doesn't only have changing governors, there's also economic and demographic data that changes over time, etc.

And I produce dozens of huge datasets that share the same geometric basis.

 

Now, if a table relate could just understand combining chronology between shape and table entry, everything would be fine. The SQL behind it is no rocket science...

Tags (2)
2 Comments
JonathanNeal

Does this documentation answer your question.  This is implemented in ArcGIS Pro.
Get started with time—ArcGIS Pro | Documentation 

WernerStangl

No, that does not solve the issue. The documentation features cases of

a)Static geometry and temporal change in attribute

b)Temporal change in geometry and static attribute

The problem that needs solving is temporal change in geometry and (independent) temporal change in attribute. I find nothing that tackles this issue.