elasticsearch - Co-locating related entities on the same shard -

how 1 co-locate related entities on different indexes (or different types on same index), both on same shard?

for example, lets there 2 entity types:

customer  orders 

in order enhance performance, orders entities related specific customer should located on same shard customer entity itself.

how done?

thanks

you should explicitly add routing value when index each document stored on same shard. possible if types exist in same index.