V$LOCK Missing Information

In our first BCOUG Tech Day conference, I presented my session “Look Inside the Locking Mechanism”. I presented this topics before a few times and prepared a few demos to show different locking scenarios.

During the BCOUG Tech Day I did the same, while the only difference was that for the demo I used Oracle 12.2 PDB (I think in previous times I always used 11.2). During one of the demos I noticed something strange.

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Restore Standby Database

Over the years I ran into all kind of weird and wonderful backup and restore scenarios. This case has challenged me for a while now and I finally had the chance to check it properly and figure out what’s going on. So here is the story.

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Did You Know #25 – Archives in FRA

One of my clients is restoring their database backup to another server for some testing. They do it periodically so we can also verify that the backup is good (which is great!). In a few cases, after the restore I saw that the restored database has an incarnation that the original database doesn’t have (and not the one created by the “open resetlogs” after the recovery). This actually caused a problem during the restore, but this restore has a few issues (I started a post about that as well).

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Importing Into Existing Tables

I did some testing with impdp for a client. They asked me to write a procedure to import a set of tables from a production environment to a testing database. The import will include only a few tables, but not all, and will be performed to an already existing test environment that contains a full schema. And this process should be performed on a regular basis, so I looked for the best and easiest solution.

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Impdp Resumable Mystery

Resumable operations are operations that can be suspended instead of failing, allowing us to fix the problem and resume the operation. When importing data using impdp, if (for example) a tablespace gets full, instead of failing the entire import (and force us to restart it from the beginning), we can identify that and add some space to the tablespace while the import is waiting.

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