The US Census makes available the TIGER Shapefiles for geographic area like States, Counties, Tracts, etc. (https://www.census.gov/geo/maps-data/data/tiger-line.html). They also supply an API for accessing the survey data. (http://www.census.gov/data/developers/data-sets/acs-survey-5-year-data.html).
I assumed you would be able to simply pass over the GEOID value to this API and get the detail for the the provided geography. Yet is seems the only way is to construct a URL is with the geographic hierarchy like so:
http://api.census.gov/data/2013/acs5?get=NAME,B01001_001E&for=tract:000100&in=state:01+county:073.
It would appear the shapefiles do provide the necessary data to construct this URL but passing GEOID would be so much simpler.
1) Is this possible to use this API providing only GEOID and am I missing it?
2) Am I overlooking something that would not make this possible? For instance, GeoIds not being unique across all geographies.