2022-5-3 &0183; Performance issues after upgrade to 19c Hi, we have run into performance issues after upgrading to Oracle 19c (19.14). For some SQL querys the optimizer will no longer create execution plans similar to them in Oracle 11g (11.2.0.4) resulting in extreme slow performance (up to a factor 1000 times).The update was done by performing new. 8 WHITE PAPER The Optimizer in Oracle Database 19c ADAPTIVE QUERY OPTIMIZATION Adaptive Query Optimization is a set of capabilities that enable the optimizer to make run-time adjustments to execution plans and discover additional information that can lead to better statistics. This new approach is extremely helpful when existing statistics. Prior to Oracle 10g, the data dictionary was optimized to use the Rule-Based Optimizer (RBO). By default the dictionary had no statistics and queries used RBO or CBO (Cost Based Optimizer) if hints were present in the underlying dictionary views. With large databases, this tended not to scale and so some queries against the data dictionary. Second, if objectkey can contain NULL values Oracle won't use the index . quot;> 2010 f150 caliper bolt torque; scooter moped 50cc; diy foundation repair pier and beam; heather poe; pine valley new jersey; what happens if you call the cops for no. There are two metrics that allow us to monitor the current used and free bytes of each tablespace oracledbtablespacebytes. oracledbtablespacefree. By monitoring the available space in tablespaces, you can plan and implement increases in disk and scale up the resources of your database before they are full.