Consider changing region code selection to match existing region code annotations

[critzo]

While exploring the new ?country= and ?region= options in the Locate API, I was attempting to use region options such as:
"US-MD", "US-CA", "GB-ENG", or "IE-C"

While the US locations work as expected, the two non-US region codes do not, instead defaulting to nearest geographically to my client. Upon further investigation, it seems the ISO-3166-2 region codes in the Natural Earth Regions dataset used by Locate do not contain all first level region codes in the spec. It seems that it includes many second level region codes.

I don't have a recommended solution to replace the current query for these regions at the moment, but will help research.

Noting also that this isn't a blocking issue on anything, as country is very useful as is. region would allow server selection with more geographic precision, but it's fine for my needs currently to use country.

[laiyi-ohlsen]

First task: document

[mattmathis]

For prior effort see:
https://docs.google.com/document/d/1k8XaricYHvfLW_3w4kVmHLx24e76xb0Tci6zZcYxEas/edit#heading=h.y4rfexmplto1 and
https://docs.google.com/spreadsheets/d/12qTdd_baEvH51EuPiNjmBdtip6Ua-rCyHiUUkmJbfLs/edit#gid=0

[stephen-soltesz]

@mattmathis I recognize the doc, is the spreadsheet the result of your queries? Would you add the queries used to generate the sheet to that spreadsheet?

[critzo]

@stephen-soltesz this spreadsheet was created manually, perhaps after basic grouping of region codes in queries. I don't think I have the queries anymore, but I can assist with re-creating them or writing new ones based on our more recent conversations.

[stephen-soltesz]

Got it. Thank you @critzo -- I'll keep that in mind when the time comes.

[mattmathis]

The following query approximate the needed translation
https://console.cloud.google.com/bigquery?sq=581276032543:c88022cbb392449c96e071a9b4561d12