A warning on Oracle-L from Chris Dunscombe: If you’ve got a large stats history – with lots of histogram data – then the upgrade could take an unexpectedly long time. Presumably the same is true if you upgrade from 184.108.40.206 (or earlier) to 12c.
Oracle 12c has many great features for DBAs and Developers; I’ll be talking about more features 12c in future articles (watch this space).
Edition-Based Redefinition made its debut in Oracle 11g and provides an ability to significantly reduce downtime due to changes in PL/SQL and/or SQL. Oracle 12c removes some limitations present in 11gR2 implementation of EBR:
Materialized Views are not-editionable; but, Oracle 12c allows them to depend upon editioned objects with a new clause and new syntax for ENABLE QUERY REWRITE. The EVALUATE USING clause indicates that a referenced object is editioned (editioned objects are invisible otherwise). ENABLE QUERY REWRITE may be limited to selected editions. The new Materialized View CREATE/ALTER syntax looks something like this:
My provisional agenda for Training Days 2014
3:15 I present “Selectivity and how Oracle calculates it”
8:30 – 9:30 (Difficult choice) Iordan Iotzov – How sure is the optimizer about its cardinality estimates
11:15 – 12:15 (Difficult choice) Andy Colvin – Common Exadata mistakes
13:15 – 14:15 Jeff Smith – Oracle Careers panel discussion
14:30 – 15:30 I present “The revolution in histograms”.
16:00 – 17:00 Terry Sutton – “Now what’s up with dbms_stats”
8:30 – 9:30 Alex Fatkulin – Why you may not need offloading
9:45 – 10:45 Jeff Jacobs – SQL Performance anti-patterns
11:15 – 12:15 Alex Gorbachev – Hadoop for Oracle Database Professional
13:30 – 14:30 Bjoern Rost – The ins and outs of Flashback Data Archives
Then it’s off to the airport before the show is over to get my flight home.
photo by Steve Jurvetson
I’m off on for a couple weeks for paternity leave! Actually started on Saturday night a week ago with the beautiful, stressful, exciting, fast birth of our second son. What a gift.
It’s a little over a month since Fedora 20 was released, but during a terrible bout of insomnia last night I decided to upgrade my desktop PC.
The upgrades using “fedup” worked fine for the previous releases (Fedora 18, Fedora 19). Unfortunately, it failed abysmally for the upgrade to Fedora 20. I tried a few times, but I was not able to troubleshoot it, so I gave up and did a reinstall.
I’ve got an SSD for the system drive, but keep almost everything of importance on a second drive (and a backup drive). I tend to do most things in VMs, so I ended up doing the following:
Got a massive day of goodies coming to anyone in Perth..for absolutely no cost – just your time and your enthusiasm.
There’s something for
See you all there …
So…the future is container databases ?
Cool ! I’ll create all my databases as container databases….I’m so happy….until
SQL> CREATE FLASHBACK ARCHIVE longterm TABLESPACE demo RETENTION 1 MONTH; CREATE FLASHBACK ARCHIVE longterm TABLESPACE demo RETENTION 1 MONTH * ERROR at line 1: ORA-65131: The feature Flashback Data Archive is not supported in a pluggable database.
It is documented but seriously….that’s not so flash :-)
Yeah yeah, you can argue with me about backward compatibility, but I’m so glad someone snuck this into 12c…
SQL> grant resource, connect to demo identified by demo; Grant succeeded. SQL> select privilege 2 from dba_sys_privs 3 where grantee = 'DEMO'; PRIVILEGE ---------------------------------------- UNLIMITED TABLESPACE
SQL> grant resource, connect to demo identified by demo; Grant succeeded. SQL> select privilege 2 from dba_sys_privs 3 where grantee = 'DEMO'; no rows selected
This is just a temporary note to let people know I’ve added an update to my Virtual Stats article, highlighting a possible performance threat when you gather stats.
I’ll be deleting this note in a couple of days, so I’ve disabled comments and pingbacks