During a performance problem I had with a query I wanted to create an index on the table. Since this was a large table I wanted the index to include all the needed columns so I won’t need to access the table at all. The query also used GROUP BY and MAX, so I thought a descending index would be best, as it will easier for Oracle to find the highest value (as it will be the first one).
When you create a job using DBMS_SCHEDULER.CREATE_JOB you can specify a schema for the job (job_name => ‘my_schema.my_job’). What does it mean?
It’s been about a year since Oracle decided to change their database version schema, from version with a couple of releases (e.g. 12.1 is 12cR1 and 12.2 is 12cR2) to a single annual version (e.g. 18c and 19c). Now, when 18c is stable and 19c is here on the cloud and Exadata and almost here on-premises, I thought it’s a good time to revisit this topic.
Since Oracle started supporting ANSI joins in 9i, the Oracle community was divided into two groups: one loved it and tried to convince everyone to use it, and the other hated it and has never switched. As you probably understand from the title, I’m in the second group, and this is why.