| ▲ | sgarland 8 hours ago | |
Because a city/region/state can be uniquely identified with a postal code (hell, in Ireland, the entire address is encapsulated in the postal code), but the reverse is not true. At scale, repeated low-cardinality columns matter a great deal. | ||
| ▲ | virissimo 6 hours ago | parent | next [-] | |
There are ZIP codes that overlap a city and also an unincorporated area. Furthermore, there are zip codes that overlap different states. A data model that renders these unrepresentable may come back to bite you. | ||
| ▲ | pbnjay 6 hours ago | parent | prev | next [-] | |
FYI this is not true in the US. Zip codes identify postal routes not locations | ||
| ▲ | lucyjojo 2 hours ago | parent | prev | next [-] | |
these kinds of things are almost never true in the real world. | ||
| ▲ | bdangubic 4 hours ago | parent | prev [-] | |
saying zipcodes uniquely identify city/state/region is like saying John uniquely identifies a human :) | ||