To: pgsql-sql@lists.postgresql.org
From: Thomas Kellerer <shammat@gmx.net>
Subject: JSON path query returns duplicate values
Message-ID: <1bbaff39-e7be-c579-779f-4ead5b47ac57@gmx.net>
Date: Mon, 21 Dec 2020 10:43:18 +0100
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Hello,

I wonder why this query

   select jsonb_path_query_array(col, '$.**.itemName')
   from (
     values ('{"items": [{"itemName": "a", "items": [{"itemName": "b"}]}]}=
'::jsonb)
   ) as t(col)

returns each itemName twice: ["a", "a", "b", "b"]

I would have expected: ["a", "b"]

Thomas