When we say “database” today we are probably talking about persistent storage, relational tables, and SQL. But most of the things we store and search for are still just numbers or strings.
And we used this distance data to guess similar words based on their distances to the same word.
A vector database interrogates the same space as the model which generated the embeddings.
So for fault tolerance, vector databases can use replication or sharding, and face the same issues between strong and eventual consistency.