If you read my post Restoring Standby Database, you know that one of the problems I had was that the new control file refused to open the database with resetlogs even though the database was consistent.
Even after years of working with something, you can always learn new stuff. Today I tried to create a standby database using the duplicate command. When you duplicate a database you need to connect to both instances (primary as target and standby as auxiliary) using SQL*Net (and not “/”). Since the standby is in nomount, the listener blocks connections to it, so when trying to connect to it using the listener we get “ORA-12528: TNS:listener: all appropriate instances are blocking new connections”.
Every day you can learn something new, even after 20 years in the field. For some reason, I was always under the impression that within a single schema, objects must have a unique name. Apparently, this is not the case.
During OOW17 a customer ran into a wrong result issue in 18.104.22.168, which is very bad. I diagnosed this and found out that it happens because of bloom filter, so we just disabled that and it was solved. But I still opened an SR so Oracle can find and fix this bug.
When Oracle are adding a new feature to the database, they usually add a parameter to control it. Sometimes, after adding feature and the parameter, they realize that the parameter they chose for controlling the feature is not suitable. It might be confusing, or too general or something else. In these cases they change the parameter in the following version.
Starting with Oracle 12.1 we can export views as tables. This means that the export will contains a “create table” command and its data, while the original object was actually a view.
The LIKE operator is a very useful one. It is used to match strings with partial match while using the underscore (‘_’) as a single character wildcard and the percentage sign (‘%’) as multiple character wildcard.