Subject: Pg18 Recursive Crash

From: Paul Ramsey <[email-masked]>
Date: Mon, 16 Dec 2024 09:50:39 -0800

Apologies if this is already reported, but there’s a crasher in recursive queries at the head of the current development that happened to be exercised by our regression suite. Here is a core-only reproduction.

CREATE TABLE foo (id integer, x integer, y integer);
INSERT INTO foo VALUES (1, 0, 1);
INSERT INTO foo VALUES (2, 1, 2);
INSERT INTO foo VALUES (3, 2, 3);

WITH RECURSIVE path (id, x, y) AS (
    SELECT id, x, y FROM foo WHERE id = 1
    UNION
    SELECT foo.id, foo.x, foo.y
    FROM path, foo
    WHERE path.y = foo.x
)
SELECT 'crash', id, x, y FROM path;

Thanks!
ATB,
P