Message-ID: <d180d17c-c48c-762e-f647-48da195f3272@postgresfriends.org>
Date: Tue, 26 Sep 2023 17:31:11 +0200
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Subject: Re: JSON type unsupported
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To: Erki Eessaar <erki.eessaar@taltech.ee>,
 "pgsql-docs@lists.postgresql.org" <pgsql-docs@lists.postgresql.org>
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From: Vik Fearing <vik@postgresfriends.org>
Cc: Peter Eisentraut <peter@eisentraut.org>
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On 9/26/23 11:33, Erki Eessaar wrote:
> Hello
> 
> According to Appendix D. SQL Conformance
> 
> https://www.postgresql.org/docs/current/unsupported-features-sql-standard.html
> 
> the feature T801 JSON data type is unsupported. However, PostgreSQL has data types JSON and JSONB. Here (http://peter.eisentraut.org/blog/2023/04/18/postgresql-and-sql-2023) it is also said that T801 is supported.
> 
> Perhaps there are some technical details that I am not aware of. However, I wanted to point this out.

Thank you for pointing this out.  Peter's blog is slightly misleading in 
that we do have the JSON data type, but the T801 feature is far from 
complete.

For example, we do not have the JSON_SERIALIZE(), JSON()[1], 
JSON_SCALAR() functions.  We don't have the IS JSON predicate, or a few 
other things hiding behind T801.

All in all, I would not say we support the JSON data type the way the 
standard intends, and therefore we should not claim to support T801.


[1] This is a fully specified parsing function, not just a cast like we 
have today.
-- 
Vik Fearing