Re: SQL/JSON query functions context_item doc entry and type requirement

On Thursday, June 20, 2024, David G. Johnston <david(dot)g(dot)johnston(at)gmail(dot)com>
wrote:

>
>> >
>> > > As for table 9.16.3 - it is unwieldy already. Lets try and make the
>> core syntax shorter, not longer. We already have precedence in the
>> subsequent json_table section - give each major clause item a name then
>> below the table define the syntax and meaning for those names. Unlike in
>> that section - which probably should be modified too - context_item should
>> have its own description line.
>> >
>> > I had posted a patch a little while ago at [1] to render the syntax a
>> > bit differently with each function getting its own syntax synopsis.
>> > Resending it here; have addressed Jian He's comments.
>> >
>> > --
>>
>
> I was thinking more like:
>
> diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
> index c324906b22..b9d157663a 100644
> --- a/doc/src/sgml/func.sgml
> +++ b/doc/src/sgml/func.sgml
> @@ -18692,8 +18692,10 @@ $.* ? (@ like_regex "^\\d+$")
> <entry role="func_table_entry"><para role="func_signature">
> <indexterm><primary>json_exists</primary></indexterm>
> <function>json_exists</function> (
> - <replaceable>context_item</replaceable>,
> <replaceable>path_expression</replaceable> <optional>
> <literal>PASSING</literal> { <replaceable>value</replaceable>
> <literal>AS</literal> <replaceable>varname</replaceable> } <optional>,
> ...</optional></optional>
> - <optional> { <literal>TRUE</literal> | <literal>FALSE</literal>
> |<literal> UNKNOWN</literal> | <literal>ERROR</literal> } <literal>ON
> ERROR</literal> </optional>)
> + <replaceable>context_item</replaceable>,
> + <replaceable>path_expression</replaceable>
> + <optional>variable_definitions</optional>
> + <optional>on_error_boolean</optional>)
> </para> empty semantics should be the same as json_query.
>
>>
>>
The full first draft patch for this is here:

https://www.postgresql.org/message-id/CAKFQuwZNxNHuPk44zDF7z8qZec1Aof10aA9tWvBU5CMhEKEd8A@mail.gmail.com

David J.