Did You Know #26 – Restoring Standby Control File

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.

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Did You Know #24 – Blocked Instances

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”.

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Did You Know #22 – Reproduce SQL Issue

During OOW17 a customer ran into a wrong result issue in 11.2.0.4, 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.

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Did You Know #21 – Adaptive Features

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.

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