I have two collections Post (belongs to posts database) and User (belongs to account database). My requirements to do join on these two collection. But I am unable to reproduce my requirements.
Hi Muhammad_umer_Farooq
By “joining” you mean running one single query over the different collections in the different databases? If yes I am afraid this is not possible directly across different databases. If the two collections are in the same database, you can use the aggregation operator $unionWith to include another collection in your current aggregation pipeline.
Only if you host your databases on Atlas you can add your databases to a Data Lake and then run queries across multiple clusters and databases. But if you are running an on-prem instance, this is not possible.
Hello,
Is there any way to use connect two collections belonging to two different databases? The way we use referencing with"ref" to relate two collections in a database, can I relate two collections somehow belonging to two different databases?
thanks in advance : )