A few weeks ago, while doing PL/SQL code review, I came across this gem: Of course upon seeing that, my head exploded. Some things cannot be unseen 🙂 While this is an extreme example, I see plenty of other examples of WHEN OTHERS abuse. This one would return “John Doe” if you ran out of Read More »
OK, I have successfully opened my database. I am in a lot better position than I was I was a few days ago. But what about my priceless Dilbert collection? It is not like I could just go to dilbert.com and download them again, could I? SQL> select count(*) from dilbert; ORA-00604: error occurred at Read More »
Does anyone notice a pattern here with the post titles? Anyway, I was loading my priceless collection of Dilbert strips into my database when it crashed and burned: Trying to restart the database, my undo tablespace is gone: SQL> startup ORACLE instance started. Total System Global Area 2499805184 bytes Fixed Size 2927480 bytes Variable Size Read More »
Comments Off on The Importance of DBA_ROLLBACK_SEGS – 2 of 3 Yes, the original post title said “The Importance of DBA_ROLLBACK_SEGS -1 of 2”. The second part was supposed to be where I clobbered my undo tablespace and had to use _CORRUPTED_ROLLBACK_SEGMENTS. Apparently I can’t even clobber my tablespaces right. My evil plan was simple: Read More »
Unless you have been a DBA for more than 10 years, you might not have even heard of DBA_ROLLBACK_SEGS. Back in the days of Oracle6 and Oracle7, when there was no Interwebs and every kid had to walk to school uphill both ways in the snow, Oracle had rollback segments. Before we had undo tablespaces, Read More »
Everyone knows the story of the Titanic. She hit an iceberg on her maiden voyage which ruptured 5 of her 16 watertight compartments. Like a RAID array, her hull was designed with redundancy in mind, and could afford the failure of up to 4 of the compartments. Unfortunately the collision damaged the 5 forward compartments, Read More »