Unique Identifiers (dcid)
Every entity in Data Commons (DC) has a unique identifier, called ‘dcid’. So, for example, the dcid of California is ‘geoId/06’ and of India is ‘country/IND’. dcids are not restricted to entities; statistical variables also have dcid, for example the dcid for the Gini Index of Economic Activity is ‘GiniIndex_EconomicActivity’.
Answers to questions like ‘what are all the cities in California?’ is a set of dcid for the cities. To facilitate joining DC entities with non-DC data, Data Commons stores the various unique IDs (e.g., FIPS, Wikidata ID, Google Maps place ID, etc) used to reference places in different sources. See the sample queries about Joining DC with your own data for some examples.
You can find the dcid for a place by searching for it in the Place Explorer tool.