FROM record_links rl1
LEFT JOIN record_links rl2 ON (rl1.to_table = rl2.from_table AND rl1.to_id = rl2.from_id)
WHERE rl1.from_table = 'oe' AND rl2.to_table = 'ar'
+ UNION
+ SELECT rl1.from_id, rl3.to_id
+ FROM record_links rl1
+ JOIN record_links rl2 ON (rl1.to_table = rl2.from_table AND rl1.to_id = rl2.from_id)
+ JOIN record_links rl3 ON (rl2.to_table = rl3.from_table AND rl2.to_id = rl3.from_id)
+ WHERE (rl1.from_table = 'oe') AND rl2.to_table = 'ar'
) rl
LEFT JOIN ar ON ar.id = rl.to_id