format('
WITH RECURSIVE _ancestors(id, ancestors) AS (
SELECT
item.id AS id,
ARRAY[item.ancestor_id] AS ancestors
FROM items AS item
%s[...]
', condition);
SELECT * FROM ancestors('WHERE item.id = 62324721');
Just keep in mind that this opens up a huge SQL-injection hole in your database. Depending on how its called you might want to validation the input text for both whitelist and blacklist items before executing it.
David J.
