Depends on what you mean. There are databases that are mostly handled by the hosting firm. MS Azure can be used in failover mode and you can scale up to more po

Depends on what you mean. There are databases that are mostly handled by the hosting firm. MS Azure can be used in failover mode and you can scale up to more powerfull "servers" without taking the application down. Sql databases are normally hard to scale-out over many servers and often require some rewriting of the application to do scale-out. IBM Cloudant can scale-out to many servers that are all handled by IBM. I'm sure a lot of other cloud based documentdatabases can do this too. Regarding why it hasn't become really popular yet organizations are generally very slow to change their data storage solutions. Changing to nosql from a relational database also requires a large rewrite of the system and it is not only upsides of going in this direction (some says that it is almost only downsides). It is for exmaple usually harder to get acid guarantees from a distributed db and it may be harder to create (secondary) indices.