In-memory databases are becoming mainstream. All the major database vendors and many startups today offer in-memory database solutions that provide an order-of-magnitude performance increase over disk-based RDBMS.
Volatile memory is available for $6-7 per GB (as of November 2016), and the latest 8-socket servers can support up to 24TB of RAM, meaning that in-memory technology is within reach for most organizations and applications.
So why not to use an in-memory database?
If you ask many industry experts, even in late 2016 in-memory databases are not for everyone. Here are three common use cases which are widely thought not to be suited for in-memory...
Read more about why for even these mainstream scenarios, In-Memory Database can be extremely relevant.