From ce0689941679c55bb22c4a9206fb792fa2dd909e Mon Sep 17 00:00:00 2001
From: ilmar yunusov <tanswis42@gmail.com>
Date: Tue, 18 Nov 2025 16:30:22 +0500
Subject: [PATCH] doc: Clarify IS JSON UNIQUE KEYS behavior

---
 doc/src/sgml/func/func-json.sgml | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/doc/src/sgml/func/func-json.sgml b/doc/src/sgml/func/func-json.sgml
index 1ec73cff464..ccb23dcdcb2 100644
--- a/doc/src/sgml/func/func-json.sgml
+++ b/doc/src/sgml/func/func-json.sgml
@@ -893,10 +893,15 @@
         parsed as JSON, possibly of a specified type.
         If <literal>SCALAR</literal> or <literal>ARRAY</literal> or
         <literal>OBJECT</literal> is specified, the
-        test is whether or not the JSON is of that particular type. If
-        <literal>WITH UNIQUE KEYS</literal> is specified, then any object in the
-        <replaceable>expression</replaceable> is also tested to see if it
-        has duplicate keys.
+        test is whether or not the JSON is of that particular type.
+        The optional <literal>WITH</literal> or <literal>WITHOUT</literal>
+        <literal>UNIQUE KEYS</literal> clause controls an additional test
+        on duplicate object keys.  Specifying <literal>WITH UNIQUE KEYS</literal>
+        requires that no object contained in the
+        <replaceable>expression</replaceable> (recursively) have duplicate keys.
+        Specifying <literal>WITHOUT UNIQUE KEYS</literal>, which is also the
+        default, disables this additional test; it does not require duplicate
+        keys to be present.
        </para>
        <para>
 <programlisting>
-- 
2.52.0

