Type validation for one. The reduced chance that a client has put some backwards format in there like MM-DD-YYYY (or DD-MM-YYYY for that matter) or just an invalid date completely.
You might as well ask what native numeric or boolean support offer over just jamming stuff in a string in an agreed format. Some might argue that dates are a compound value so differ from atomic types like a number, but they are wrong IMO as a datetime can be treated as a simple numeric¹ with the compound display being just that – a display issue.
Others will point out that JS doesn't have a native date/datetime/time type, but JSON is used for a lot more that persisting JS structures at this point.
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[1] caveat: this stops being true if you have a time portion with a timezone property
Maybe it is "just us", maybe it is part of the general shitness you point out, maybe it is the lack of literal representation (even VB and relatives had one) other than an ISO8601 string, but dates don't feel native like simpler types, arrays, objects, fictions, …
> So what I'm reading here is that you don't need types to be supported natively in order to serialize to JSON.
Yes. But not absolutely needing something does not mean it isn't (or wouldn't be) exceptionally useful to have.
What it gets you is not having to deal with breakage when someone doesn't know the difference between ISO8601 and RFC3339 or, in fact, `date` strings. Shuffle all that mess off down the stack to where someone else has made one decision, once, rather than having to relitigate it every time.
JSON will never have datetime support, since Javascript does not have datetime literals (and that's a good thing given how horrible the Date object is).
Probably more importantly, all of that and still not proper datetimes in sqlite.
Also even more so no domains (for custom datatypes).
> Probably more importantly, all of that and still not proper datetimes in sqlite.
Home Assistant recently did a ton of changes to work around the issues caused by this.
The short story is that they stopped storing timestamps as 'timestamp' datatypes and started storing them as unix times stored in numeric columns. Since timestamps turn into strings in SQLite, this was a huge improvement for storage space, performance, etc.
The problem is that this change also affects databases which have a real datetime datatype. So PostgreSQL, which internally stores timestamps as unix times, is now being told to store a numeric value. To treat it as a timestamp you have to convert it while querying. Since I used PostgreSQL for my Home Assistant installation, this feels like a giant step backwards for me.
I wish that they had used this change as an opportunity to refactor the database code a bit so that they could store timestamps as numeric for SQLite, but use a real timestamp datatype for MySQL and PostgreSQL. I'm sure that this isn't a simple thing to do though.
Generally speaking... DateTime/TimeStamp fields between databases are in general treated differently either in practice or purpose much of the time. When migrating from one database to another, this is almost always an issue.
I don't know what "appropriate" or even "beyond the scope" mean in this context but, having in mind that datetime data needing to be stored is a fact of life that's not going away then I'd say yes, it does belong in JSON.
Wrong, there's no datetime there. Only integer can be used for it in a more space-saving manner. But that means you have to convert and invoke calculation functions. It's error-prone.