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create table categories ( id int generated always as identity primary key, parent_id int references categories(id) on delete cascade, name text ); insert into categories(parent_id, name) values (null, 'Root'), (1, 'Sub-root1'), (1, 'Sub-root2'), (3, 'Sub-sub-root3'); with recursive cat_tree as ( select id, name from categories where id = 1 union all select categories.id, categories.name from categories join cat_tree on cat_tree.id = categories.parent_id ) select * from cat_tree;