Oracle 19c: Real-Time and High-Frequency Statistics Collection

OGB EMEA 13.10.2020

Keeping statistics up to date is critical to Oracle database performance and stability. Both features aim to address the challenge of using data that has been significantly updated before the statistics maintenance window has run again. Interestingly, these features are only available on Engineered Systems. However, that is a commercial decision, not a technical one.
Real-time Statistics augment existing statistics. However, they are not quite as real-time as the name suggests. To keep their implementation lightweight they use the table monitoring mechanism, this limits the information that can be collected.
High-Frequency Automatic Optimizer Statistics Collection is effectively a never-ending statistics maintenance window. As your data and statistics change, so there are opportunities for SQL execution plans, and therefore application performance to change. DBAs and developers need to be aware of the implications.