Permintaan rekursif di Oracle

Di Oracle ini mudah dilakukan menggunakan CONNECT BY

select message_id, parent_id, message_content
from messages
start with message_id = 97 -- this is the root of your conversation
connect by prior message_id = parent_id;

Ini berjalan pohon dari atas ke bawah.

Jika Anda ingin menelusuri pohon dari satu pesan ke akar, ubah start with dan connect by bagian:

select message_id, parent_id, message_content
from messages
start with message_id = 100 -- this is the root of your conversation
connect by prior parent_id = message_id; -- this now goes "up" in the tree