There is no one-size-fits-all break-even point for indexed versus table scan access. If only a few rows are being accessed, the index will be preferred.
If almost all the rows are being accessed, the full table scan will be preferred. In between these two extremes, your “mileage” will vary.
This note describes the procedure used to perform a minimal downtime platform migration from Windows to Linux as well as a database upgrade from Oracle 126.96.36.199 to Oracle 12c (188.8.131.52).
We create a Data Guard physical standby database using the DUPLICATE FROM ACTIVE DATABASE feature, followed by a switchover and then we activate the standby and make it a primary database. Finally we upgrade the database to 12c using the catctl.pl perl utility with the parallel upgrade option.
Here is my story about the flight simulator called X-PLANE. I would like to share my experience about this flight sim, my desktop’s hardware specification, controllers that I’m using, and application settings for an optimal performance.
I’m working on Oracle database migration project where customer have chosen commodity x86 hardware with RHEL6 and EMC storage.
A recent thread on the OTN database forum supplied some code that seemed to show that In-memory DB made no difference to performance when compared with the traditional row-store mechanism and asked why not. (It looked as if the answer was that almost all the time for the tests was spent returning the 3M row result set to the SQL*Plus client 15 rows at a time.)