The query goes like this
SELECT ... FROM A RIGHT OUTER JOIN ( SELECT b1, b2, b3 FROM B ) AS BB INNER JOIN ( SELECT c1, c2, c3 FROM C ) AS CC ON BB.b1 = CC.c1 INNER JOIN D ON CC.c2 = D.d2 ON A.a2 = D.d2
That query above returns a table. The problem is the syntax is so weird to me. I can't read and make sense of it the way the writer intended. I didn't even know which table is on which side.