After speaking about mutex waits last year, this time DOAG accepted my lecture “Oracle Architektur – nicht nur für Einsteiger” about Oracle Database basic architecture for this year’s DOAG Konferenz 2013 in Nürnberg. It will be the first lesson in a brand-new stream of the conference: The so-called “Einsteigerpaket” (beginners package) allows […]
How NLS settings can affect Oracle’s join behavior – v$ example
Recently, I had a problem with accessing Active Session History being not fast enough on Oracle Database 11.2 and 12.1. Looking at the explain plan, wow, no doubt why: Accessing two fixed tables with TABLE ACCESS FULL and joining them with NESTED LOOP. This couldn’t have been “works as designed”, it would render gv$active_session_history nearly […]
Oracle SQL: Optimizing a WHERE predicate inequality with a Function Based Index
Intro Recently, on Oracle 11.2.0.3, I saw a join of three tables, using three times TABLE ACCESS FULL and HASH JOIN, without an obvious reason. During separating and understanding its components, the following scenario turned out to be the culprit. select * from CARDTEST where OBJECT_ID<DATA_OBJECT_ID; The optimizer is unable to calculate the cardinality of […]
Oracle Database 12c Release 1 available
Since today, Oracle allows downloading the newest release of the Database product 12c via http://edelivery.oracle.com So far I only can see it for the Linux platform, and docs are still missing. But this may change rapidly. Take care Martin Klier […]
Oracle Support allows SR details in notification emails
Yes, they did it! Finally, last night’s announcement from Oracle Support brought a long-missed feature: We can opt-in to get Service Request details in MOS’ notification emails. It’s of great benefit when you are on the road, no need to log in to the far-famed support portal. This is how the CUA has to allow […]
ORA-600 [kokiasg1] – reasons and workaround
Last days, I had an interesting issue with a customer’s test database. The DB crashed, after manually but unintentionally corrupting the SYS schema (dropping an unknown number of objects). Restarting the instance (open) ended with: ORA-00600: internal error code, arguments: [kokiasg1], [], [], [], [], [], [], [], [], [], [], [] Our quick fix […]
Oracle Real World Performance Tour 2014 with Tom Kyte and friends in München (Munich)
The German Oracle User Group (DOAG Deutsche Oracle Anwendergruppe) announced Munich as a location of the Real World Performance Tour 2014 with Tom Kyte, Senior Technical Architect ORACLE Server Technology Division, ORACLE Vice President Graham Wood, Architect Server Technologies Andrew Holdsworth, Senior Director Real World Performance Server Technologies Location: Munich (Details coming soon) Date: February […]
Upcoming DBA in Team Oracle Germany? :)
I’m no fan of preselecting kid’s ways of life. But I couldn’t resist bringing a T-Shirt from OpenWorld back to Germany. Now since it fits Maxi, I’m just loving it. 🙂 The other picture is my teammate Benedikt as Maxi’s cushion. 🙂 Please: Let […]
Oracle SQL Developer connection storm at startup
Oracle SQL Developer (tested with version 3.2.20.09) does some unwanted network connection testing against all configured connections (by TNSPING). We noticed that it causes a kind of unwanted “inverse” connection storm to all configured databases, when we start the SQL Developer. It’s not restoring aborted connections or stuff like that, all was quit before stopping […]
DOAG Webinar: ORACLE Datenbank Architektur – nicht nur für Einsteiger (German Language)
On Friday, 08/03/2013, I’ll present an online lecture about Oracle Architecture for the DOAG (Deutsche Oracle Anwendergruppe, German Oracle User’s Group) and the DOAG SIG Database. Link: http://www.doag.org/termine/termine.php?tid=454245 The lesson will contain (excerpt from TOC): Oracle Datenbank-Architektur Verbindung, Namespace(s) und Abschottung Instanz und Datenbank Alles Blöcke, oder was? Redo, Undo und was man […]