https://josef.codes/gotcha-when-using-postgres-nodatime-ef-core-and-dapper/
https://nodatime.org/3.1.x/userguide/concepts
https://www.youtube.com/watch?v=zl0h2J6a0w4
https://github.com/StevenRasmussen/EFCore.SqlServer.NodaTime
https://www.npgsql.org/efcore/mapping/nodatime.html

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Datetime with Kind UTC | timestamp with time zone
Datetime with Kind Local ou Unspecified | timestamp without time zone

timestamp without time zone (timestamp)
timestamp with time zone (timestamptz) + ajouter colonne string avec la timezone (IANA)

ZonedDateTime
It should also be pointed out that Noda Time has a representation called ZonedDateTime for this, while the .Net base class library does not have anything similar.
You would need to store both a DateTimeOffset and a TimeZoneInfo.Id value.

https://codeblog.jonskeet.uk/2019/03/27/storing-utc-is-not-a-silver-bullet/
https://codeopinion.com/just-store-utc-not-so-fast-handling-time-zones-is-complicated/

https://www.npgsql.org/doc/types/datetime.html
https://learn.microsoft.com/en-us/dotnet/api/system.datetime.touniversaltime?view=net-6.0