What is an artificial (derived) primary key?
A derived key comes from a sequence. Usually it is used when a concatenated key becomes too cumbersome to use as a foreign key. Oracle Interview Questions 1. When should you consider denormalization Whenever performance analysis indicates it would be beneficial to do so without compromising data integrity. 2. How can you determine if an Oracle instance is up from the operating system level There are several base Oracle processes that will be running on multi-user operating systems, these will be smon, pmon, dbwr and lgwr. Any answer that has them using their operating system process showing feature to check for these is acceptable. For example, on UNIX a ps -ef|grep dbwr will show what instances are up. 3. Users from the PC clients are getting messages indicating : ORA-06114: (Cnct err, can’t get err txt. See Servr Msgs & Codes Manual) What could the problem be The instance name is probably incorrect in their connection string. 4. Users from the PC clients are getting the following err
