Binary JSON format on-disk or in-memory

Couchbase Server
1

I am working on a research project comparing several document-oriented databases.

MongoDB has BSON, ArangoDB has VelocyPack, Postgresql has Jsonb,…

Does Couchbase also have its own binary format to work with JSON documents, on disk or in memory?

2

Data is typically stored as plain JSON, though binary documents can also be stored (though not manipulated). This is noted here:
https://docs.couchbase.com/server/current/learn/architecture-overview.html#about-this-section
and in more detail here:
https://docs.couchbase.com/server/current/learn/data/data.html

HTH.

3

@dh When Couchbase stores a JSON document, does it store the JSON text (possibly Snappy-compressed), or does it use some other binary JSON format internally?

I think that’s the thrust of the question, judging from the related discussion on StackOverflow.

4

@jwalker may be better placed to confirm the internals. AFAIK, it does depend on the bucket type, with Couchbase buckets being implemented with GitHub - couchbase/couchstore: couchbase storage file library

5

Certainly when couchstore is the storage, a document is just compressed using snappy, no other “re-formatting” occurs. So if a JSON document is written, it is just that JSON document stored after being snappy compressed, if a binary value is written, it is just that binary value stored after being snappy compressed.