Steve Atkins wrote:
...
Should the telephone type be able to do something such as:
SELECT * from tableFOO where telephone.areacode = 555;
Maybe, but is that useful? Maybe America is different, but my
experience in NL and AU is that you rarely care about the areacode
anyway, so why would you want to pull it out?
Strong correlation to geographical area - very useful for sales
campaigns or geolocation. Also, free numbers (aka 800 numbers
in the US) have distinctive area codes. Of course, identifying
the area code is easy in the US, but much harder (or even
meaningless) elsewhere. In other bits of the world area codes
allow you to identify mobile numbers.
It's actually quite useful to separate out both the NPA (area-code) and
NXX (prefix) in US numbers. We subscribe to data that lets us determine
lots of things for a given NPA/NXX (MSA, PMSA, lat/lon, ratecenter,
zip-codes covered, time-zone, observes daylight-saving?,
wireless/wireline, etc.)
Of course with number portability you can't rely on just the NPA and NXX
to determine whether the number is wireless but you can subscribe to
other data that lists all the numbers that have been ported from
wireless to wireline or vice-versa to fix that issue.
Cheers,
Steve
