Duplicated UN/LOCODEs

[salim-b]

There are various geographical locations that have multiple UN/LOCODEs assigned. One example is the Swiss municipality Schönenbuch that has two entries in locodes/CH.csv that only differ in the change date and the LOCODE itself (SBC vs. SOH).

This raises the following questions:

1. Why are there multiple UN/LOCODEs per entity in the first place? Are those "coding errors"?

2. Is there a "best practice" on how to handle such duplicates? Should we e.g. always take the entry with the most recent change date¹?

Footnotes

1. Although that particular heuristic wouldn't suffice to resolve all duplicates since there are entries that don't even differ in the change date but only the LOCODE. ↩