Message-ID: <f408910c-e19f-42b0-ae6a-e8bceecc3bc2@uni-muenster.de>
Date: Wed, 4 Mar 2026 12:35:17 +0100
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Subject: Re: POC: PLpgSQL FOREACH IN JSON ARRAY
To: Pavel Stehule <pavel.stehule@gmail.com>
Cc: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
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From: Jim Jones <jim.jones@uni-muenster.de>
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I reviewed the code I have nothing to add at this point. LGTM!

The tests touch a lot of different scenarios, but for the sake of
completeness I'd like to suggest adding these three cases:

-- EXIT and CONTINUE can be triggered by LOOP_RC_PROCESSING
DO $$
DECLARE x int;
BEGIN
  FOREACH x IN JSON ARRAY '[1,2,3,4,5]'
  LOOP
    EXIT WHEN x = 3;
    RAISE NOTICE '%', x;
  END LOOP;
END;
$$;

DO $$
DECLARE x int;
BEGIN
  FOREACH x IN JSON ARRAY '[1,2,3,4,5]'
  LOOP
    CONTINUE WHEN x % 2 = 0;
    RAISE NOTICE '%', x;
  END LOOP;
END;
$$;


-- Variable instead of string
DO $$
DECLARE x int; arr jsonb;
BEGIN
  SELECT jsonb_agg(i) INTO arr
  FROM generate_series(1,3) i;

  FOREACH x IN JSON ARRAY arr
  LOOP
    RAISE NOTICE '%', x;
  END LOOP;
END;
$$;


Thanks!

Best, Jim