New features are one reason to upgrade to a new Oracle release, bug fixes of known bugs are another one. With Oracle 19c, at least two bugs related to Automatic List Partitioning were fixed. I did some tests with Auto-List Partitioning on an Oracle 19.3 database.
Oracle 19c provides a set of new SQL functions for bitmap operations. They allow fast computation of COUNT(DISTINCT) expressions. What is the purpose of these functions? The Oracle documentation is very sparse, but at least it tells us that the main focus are Materialized Views on aggregated data. Let’s have a detailed look at this new feature.