DBA_EXTENTS
DBA_EXTENTS
Did you ever try to query DBA_EXTENTS on a very large database with LMT tablespaces? I had to, in the past, in order to find which segment a corrupt block belonged to. The information about extent allocation is stored in the datafiles headers, visible though X$KTFBUE, and queries on it can be very expensive. In addition to that, the optimizer tends to start with the segments and get to this X$KTFBUE for each of them. At this time, I had quickly created a view on the internal dictionary tables, forcing to start by X$KTFBUE with materialized CTE, to replace DBA_EXTENTS.
Disclaimer
The views expressed in this blog are those of the authors and cannot be regarded as representing CERN’s official position.
Blogroll
CERN update, Quantum Diaries, Careers at CERN
Christian Antognini, Karl Arao, Martin Bach, Mark Bobak, Wolfgang Breitling, Doug Burns, Kevin Closson, Cloudera blog, Wim Coekaerts, Bertrand Drouvot, Enkitec blog, Pete Finnigan, Richard Foote, Randolf Geist, Marco Gralike, Brendan Gregg, Kyle Hailey, Tim Hall, Uwe Hesse, Frits Hoogland, Hortonworks blog, Integrity Oracle Security, Tom Kyte, Adam Leventhal, Jonathan Lewis, Cary Millsap, James Morle, Karen Morton, Arup Nanda, Mogens Nørgaard, Oracle The Data Warehouse insider, Oracle Enterprise Manager, Oracle Linux blog, Oracle Multitenant, Oracle Optimizer blog, Oracle R technologies, Oracle Upgrade blog, Oracle Virtualization blog, Kerry Osborne, Tanel Poder, Planet PostgreSQL, Kellyn Pot'Vin, Pythian blog, Greg Rahn, Mark Rittman, Riyaj Shamsudeen, Chen Shapira, Carlos Sierra, Szymon Skorupinski