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Author Archives Laurent Schneider

New environment for OCM 11g

For my readers who are preparing the ocm 11g exam, the environment just changed (From 13th May 2013 onwards) Instead of using OEM 10g, you will be using OEM 11g. The upgrade exam is still using OEM 10g and DB 11gR1 (!) but I did not care installing OEM 10g and I prepared with OEM [...]

Posted 13 May 2013 § Uncategorized ‡ Comments Off °

use cron to schedule a job only once

I wrote about not using DAY OF MONTH and DAY OF WEEK simultanously in how to cron The correct method is to use 15 14 15 05 * /tmp/run-my-job But… I wrote this five years ago. Hmmm ! Not that correct then since it would run every year Ok, periodically I check for jobs are [...]

Posted 06 May 2013 § Uncategorized ‡ Comments Off ° Tagged:

Delete one billion row

To delete large number of rows, for instance rows with date until 2010, you can issue this simple statement. SQL> DELETE FROM T WHERE C<DATE ’2011-01-01′; 1’000’000’000 rows deleted Elapsed: 23:45:22.01 SQL> commit; This is perfectly fine. The table remains online, other users are not much affected (maybe they will not even notice the lower [...]

Posted 24 April 2013 § Uncategorized ‡ Comments Off ° Tagged:

SPARC Supercluster

Oracle buys Sun was an exciting accouncement 20 months ago. What did change in the Solaris/Oracle Database world? First, Oracle delivered Exadata on Sun Hardware (x86_64). Second, they delivered Exadata on Sun Solaris Operating System (x86_64). But now, they announced a combination of software and hardware that will run Oracle database faster than anything ever [...]

Posted 03 December 2010 § Uncategorized ‡ Comments Off °

connect by and recursive with (part 2)

According to the doc
The subquery_factoring_clause now supports recursive subquery
factoring (recursive WITH), which lets you query hierarchical data.
This feature is more powerful than CONNECT BY in that it
provides depth-first search and breadth-first search, and supports
multiple recursive branches. A new search_clause and cycle_clause
let you specify an ordering for the rows and mark cycles in the
recursion
As written there [...]

Posted 20 May 2010 § Uncategorized ‡ Comments Off °