Join multiple collections on multiple keys using map reduce in Mongo DB.
Anand Dayalan
I know a way to join multiple collections using a same key, and I thinks its not possible to join multiple collections on multiple keys but wondering anyone know a way to do it.
Lets say I have a collection AAA with fields A, B, and C, and I have a collection called BBB with fields B, D and E, and I have another collection called CCC with fields C, F, G.
In collection AAA field B is DB Ref for field B in collection BBB, and field C in collection AAA is a DB ref for field C in collection CCC. Now I want join these three collections like AAA join BBB on AAA.B =BBB.B , BBB join CCC on BBB.C = CCC.C.
I know that I can embed one collection in another but I have a situation where I can't embed everything but need to do a adhoc report across multiple collection. So how do I do it?
