Re: JSON Path and GIN Questions

On Sep 14, 2023, at 00:41, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:

> As far as json in particular is concerned, 8.14.4 jsonb Indexing [4]
> is pretty clear about what is or is not supported.

How do you feel about this note, then?

diff --git a/doc/src/sgml/json.sgml b/doc/src/sgml/json.sgml
index b6c2ddbf55..7dda727f0d 100644
--- a/doc/src/sgml/json.sgml
+++ b/doc/src/sgml/json.sgml
@@ -413,6 +413,13 @@ SELECT doc-&gt;'site_name' FROM websites
Two GIN <quote>operator classes</quote> are provided, offering different
performance and flexibility trade-offs.
</para>
+ <note>
+ <para>
+ As with all indexes, only operators on indexed columns are considered as
+ index qualifications. In other words, only <type>jsonb</type> operators can
+ take advantage of GIN indexes; <type>jsonb</type> functions cannot.
+ </para>
+ </note>
<para>
The default GIN operator class for <type>jsonb</type> supports queries with
the key-exists operators <literal>?</literal>, <literal>?|</literal>

Best,

David