What is our primary use case?
We are using Oracle Database In-Memory as an indirect approach to improving response times. In mixed-workload environments, we use the In-Memory column store to support OLAP-type queries without harming the latency-critical OLTP operations the systems "earn money with". This was successful for many customers throughout 12.2 and 18c.
How has it helped my organization?
It helps to build successful mixed-workload environments. Thus, for smaller setups, it's enough to have one database setup, not two, and it saves one interface in between.
What is most valuable?
In recent versions, Oracle implemented storing the In-Memory column store contents in the database, to resurrect the IMCS quicker and in a repeatable way.
What needs improvement?
One very nice side-effect is the in-memory index. If this would be developed a bit more into being configurable, users could use it as a kind of in-memory partitioning. That opens a big field of possible use cases.
For how long have I used the solution?
One to three years.
What do I think about the stability of the solution?
What do I think about the scalability of the solution?
In my experience, it scales quite well. Unfortunately, decent scale-out with RAC only works in Exadata, since Oracle relies on RDMA which is only available for InfiniBand.
How are customer service and technical support?
"It depends". If you get a good support engineer, it is a dream.
But, most times, it is not, unfortunately.
Which solution did I use previously and why did I switch?
No, since there was no other solution offering in-memory without changing the SQL syntax.
How was the initial setup?
We grew into it during beta and initial releases, so I can't answer this.
What about the implementation team?
We do implementations ourselves, so I can't answer this.
What was our ROI?
If you can save setting up an additional interface and a second DB server, investment should return immediately.
What's my experience with pricing, setup cost, and licensing?
The setup cost is not a big factor, but the engineer should have decent experience with Oracle's In-Memory system.
License cost is a factor; the benefit has to be carefully evaluated.
Which other solutions did I evaluate?
We tried several ways to offload OLAP queries from the database, especially using a second DB system.
We evaluated this product throughout the beta1 and beta2 phase.
What other advice do I have?
It is always worth testing or running a proof of concept to check its value.
Disclosure: I am a real user, and this review is based on my own experience and opinions.