I am trying to do some data cleanup and was hoping to figure out how to use Tableau's mapping to fill in missing city names. I'm operating off a less-than-perfect data set of customers, their postal codes, and the metro area they are considered to be a part of (these metros spill over state lines to include large suburban areas of influence). Unfortunately the data set is missing a number of city names but these NULL cities are surrounded by postal codes that are correctly aggregated. Is there a way to use some kind of clustering functionality with generated lat/long to fill in these missing records with the city names of the surrounding data points?
If you had exactly lat/long values, then you could use some reverse geocoding to get the city name based on that, but as it stands, you only have zip code. You might be able to write some code that looks at all the cities in a zip code then guesses one based on, but I'm not sure that would be very accurate. I don't really see any purely Tableau-based solution for this.