On 06/28/2018 06:45 PM, Nikita Glukhov wrote:
> Standard says only about returning of string (both binary and character),
> numeric, boolean and datetime types in JSON_VALUE and only about string
> types in JSON_QUERY.
What I think I noticed was that right now, in func-sqljson.sgml,
the same list of seven types (not including numeric, boolean, or
datetime) is repeated for both JSON_QUERY and JSON_VALUE. Should
the list for JSON_VALUE also mention that numeric, boolean, and
datetime are supported there? That's the description that is near
line 1067.
> Arithmetic operations in jsonpath are implemented using PG numeric
> datatype,
> which also is used in jsonb for representation of JSON numbers:
> ...
> =# SELECT jsonb '-3.4' @* '$ % 2.3';
> ?column?
> ----------
> -1.1
In a recent message[1] it seemed that PG itself relies on the
underlying C compiler behavior, at least for int and float, which
could mean that on some platforms the answer is -1.1 and on others
+1.2. But I don't know whether that is true for PG numeric, since
that is implemented much more within PG itself, so perhaps it has
a platform-independent behavior. The XQuery result would be -1.1 on
all platforms, because the standard is explicit there.
-Chap
[1]: https://www.postgresql.org/message-id/23660.1530070402%40sss.pgh.pa.us