Oracle 19c New Features: Real-Time Statistics and High-Frequency Automatic Optimizer Statistics Collection
A look at the aspects of 2 features that address the challenge of using data that has been updated before statistics maintenance runs again. Accurate statistics are critical to database performance and stability. Interestingly, these are Engineered Systems features, which is not a technical decision
A short look at the pros and cons of these new 19c features. 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.
*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 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.
Interestingly, these features are only available on Engineered Systems. However, that is not a technical decision, rather it says something about current development priorities in Oracle.