
Azure DocumentDB
5.8#21 in document databasesFree planFree planLinuxmacOSWindows
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Azure DocumentDB suits teams building applications around BSON or JSON documents that need transactions or vector search. The Free Tier may be relevant for a cluster needing up to its listed 32 GB of storage.
RethinkDB suits developers building applications that need query-result updates as data changes, including collaborative apps, multiplayer games, and real-time marketplaces. It is less suited to workloads that require full ACID support or strong schema enforcement.