Enhanced purging of the Oracle recyclebin

Introduction In the Oracle RDBMS v10, the ‘recyclebin’ for segments was introduced. If the recyelebin=on parameter is set, and a table is dropped, it is not actually dropped – it is renamed to a system-generated name. This can really help in situations where a table is accidentally dropped, as it can be easily recovered. However, […]

Collaborate IOUG 2015 Session Material

I had the pleasure and the honor of presenting “DBA 3.0 or How to Become a Real-World Exadata DBA” at Collaborate 2015 – IOUG’s annual user conference – in Las Vegas. It was a fantastic experience for me, personally, and I thoroughly enjoyed answering questions and talking about all things Exadata with the audience both during and after my […]

Clearing Unused Corrupt (Nologging) Blocks

I recently had the unfortunate experience of having to restore / recover a database that had undergone ‘nologging’ operations after the latest backup. Of course, the presence of blocks recovered through a nologging operation causes ORA-01578 errors such as ORA-01578: ORACLE data block corrupted (file # 11, block # 91658) ORA-01110: data file 11: ‘+DATADG/tollprd/datafile/toll_t01.256.849581711’ […]

Understanding UNDO

Sooner or later, every Oracle DBA will hit a problem of some sort that is related to the concept of Oracle “Undo”. The Oracle Undo performs a few very important functions in the database; these being the support of read-consistent queries and Flashback queries, supporting transactions (COMMIT and ROLLBACK), and recovering from database crashes. Along […]

Just the basics; Upgrading the Oracle RDBMS

Introduction This is the first installment of a series of shorter whitepapers that just cover the basics of a particular aspect of the Oracle RDBMS. The first one is on the subject of upgrading Oracle. After doing literally hundreds of Oracle RDBMS upgrades and patches over the past 18 years, these are my recommendations. Why […]