Check if Document exists

[Tarun_Gaur]

Hello @Jackolix ,

Welcome to The MongoDB Community Forums!

I notice you haven’t had a response to this topic yet - were you able to find a solution?
If not then can you confirm if documents exist in your collection and can you share an example document?

Also,

@Jackolix

collection.find(eq("UUID", id)).first();

Can you try your query in shell and check if you are getting the expected results?

@Jackolix

(doesn’t work)

By doesn't work do you mean that it never returns the expected value or are you seeing some other error?

@Jackolix

The error that is saw the most is that I can’t cast for example: ‘Publisher’ to ‘long’ or ‘Publisher’ to ‘Document’

Can you please share the exact error that you are getting? If it’s a casting error, then please refer to this thread which I think is related.

Additionally, I would recommend you to go through below thread and resources which includes some examples on querying database using reactive streams.

• MongoDB Java Reactive Streams help
• Quick Tour
• mongo-java-driver/driver-reactive-streams/src/examples/reactivestreams/documentation/DocumentationSamples.java at master · mongodb/mongo-java-driver · GitHub

Regards,
Tarun