Index Usage – 2

I’ve beeen a little slow in the follow-up to my previous posting on possibly redundant indexes. Before going into the slightly more complex stuff, there’s another peripheral point (but a very important one) that’s worth raising about how clever the optimizer can be. Here’s some code for to demonstrate the point:

create table t1
with generator as (
	select	--+ materialize
		rownum id 
	from dual 
	connect by 
		level <=  (more...)

Creating a Trace File from EM12

Creating a trace file from EM12c is quite easy and doesn’t require a DBA offering up the world to allow a developer or support person to perform this action.

Enterprise Manager also removes some of the syntax options that could get a developer or app support person that is less specialized in creating trace files, all the options and the knowledge of the syntax, etc. from getting into trouble, which creates an option for everyone to be successful.


amcmd> a better “du”

I discovered ASM with a RAC running on Linux Itanium and that was a big adventure. At this time there was no asmcmd. In 2005, Oracle released Oracle 10gR2 and asmcmd came into the place and we figured out how to make it work with a 10gR1 ASM. We were very excited to have a command line for ASM until… we tried it ! let’s call a spade a spade,  it was very (more...)

Simplify Oracle Tracing with Creative Scripting

Running a SQL trace is something that all DBAs do to varying degrees. Let’s say you are working on optimizing a SQL statement, and experimenting with some different hints for indexes and optimizer directives. This kind of effort typically goes something like this:

  • modify the SQL statement
  • enable tracing
  • run the statement
  • disable tracing
  • disconnect
  • retrieve the trace file
  • use a profiler to process the trace file
    this might be Method-R mrskew,Oracle tkprof, or (more...)

Webcast: Ride the Digital Wave or be Swept Underneath It

Digital disruption is changing business as we know it, yet many organizations think they'll get by on the same old strategies and technologies. 

On Thursday, Sept 17 @10am PST, join Oracle and Ventana Research to learn how to stay on top of change and ahead of the competition. Ventana CEO Mark Smith will share findings from their recent study, exploring 7 digital technologies that (more...)

Oracle Cloud : First Impressions

cloudFollowers of the blog will know I’ve been waiting to get access to the Oracle Cloud for a while. Well, I’ve finally got access to a bit of it. Specifically, the “Oracle Database Cloud Service” (DBaaS) part. :)

The Schema Service has been around for a few years and I had already tried that out, but IMHO it’s not really part of Oracle Cloud database vision*, so I was reserving my judgement until I got the real (more...)

The Hitchhiker’s Guide to the EXPLAIN PLAN Part 39: Unfriending the optimizer statistics

We can’t help attaching meaning to optimizer statistics. After all, they represent our data, don’t they? So we refresh them as frequently as possible and use the largest sample sizes that we can use. Recently, for the first time in my life, I encountered a group of DBAs who understood that statistics do not have any intrinsic meaning; that they are nothing more than a collection of numbers that influence the generation of query plans. (more...)

Planning en budgettering: “In the cloud” of beter met de voeten op de grond?

door Herman Snykers, Principal Sales Consultant bij Oracle

Cloudoplossingen duiken steeds meer op als modern alternatief, maar hebben zij zin als alternatief voor organisaties met live on-premise planning-, budgeting- en forecasting-software?

In mijn zeven jaren als EPM-consultant heb ik het geluk gehad te werken bij een aantal bedrijven met een hoog volwassenheidsniveau hebben op vlak van Enterprise Performance Management. Er wordt gewerkt met een centraal planning- en budgetingsysteem, beheerd zonder hulp van IT, geconnecteerd (more...)

Open a MOS Document by its DocID

I've always been wondering if there wasn't an easier way to view a MOS document than to go to the portal and "search" for the DocID which I already know.  Using a Firefox search plugin had been an idea for a while.  Now I finally found a few minutes to try that.  It works - find the plugin below.  Simply save it as "DocID.xml" in the searchplugins directory of your (more...)

MOS Dokumente mit DocID aufrufen

Ich habe mich immer wieder gefragt, ob es nicht eine einfachere Methode gibt, ein MOS Dokument zu oeffnen, als sich im Portal zur Suchmaske durch zu klicken um die DocID, die ich ja schon kenne, einzugeben.  Die Idee, das mit einem Search Plugin fuer Firefox zu machen, hatte ich schon lange.  Jetzt hatte ich auch ein wenig Zeit, und hier ist das Plugin.  Einfach als "DocID.xml" in "searchplugins" des Firefox-Profils ablegen, (more...)

Oracle Mobile Cloud Service is available

Oracle Mobile Cloud Service provides the services you need to develop a comprehensive strategy for mobile app development and delivery. It provides everything you need to establish an enterprise mobile strategy using innovative, persona-based tools and services. Designed to accelerate agility, speed time to market and simplify enterprise mobility while reducing costs, Oracle Mobile Cloud Service helps developers define mobile APIs and build mobile apps that connect to enterprise systems quickly and securely. It provides (more...)

Hybride Integration Technology Events

Im September finden zwei Veranstaltungen zum Thema Hybride Integrationsplattform - einer Kombination aus iPaaS und On-Premise Integration - mit vielen Demos zu Integration Cloud Service, Process Cloud Service, API Management und SAP Integration mit der SOA Suite statt.

Hybride Integration ermöglicht die Verbindung zwischen SaaS Anwendungen in der Cloud und On-Premise Systemen und stellt eine Grundlage für die Umsetzung der Digitalisierungstrategie im Unternehmen dar.

Hier geht's zur Anmeldung:

Am Dienstag, 22.09.2015 in Frankfurt/Dreieich.


Debug RemoteOperationException

  • Check agent status (Agent should be up and running - just give a restart if you doubt)
  • Stop agent before any changes., and start after !
  • Check the file/folder permissions (parent folder too)
  • Check the file/folder ownership ( , make sure your are inline with your agent installation.
  • Check privilege delegation settings
  • For NMO not setuid-root issues
  • Run that is available in your agent
  • nmo,nmhs,nmb,nmosudo,nmgsshe,nmopdpx  - these files under agent should be (more...)

SQL Experts Panel at OpenWorld

Got SQL questions ? Get them logged here, then come along to our SQL Panel at Oracle OpenWorld !

We are holding a panel session exclusively dedicated to the amazing SQL language:

SQL for Functionality, Performance and Maintainability, and its future

We often think of SQL solely in terms of how to tune it.  And whilst it is true that SQL performance is a key factor, SQL is also so much more than that.  SQL is at (more...)

Design Jams as a stimulating and creative change

We have done a lot of design jams this year and mostly they are open to anyone at Oracle, based on a particular theme or technology area.  But this summer, we ran two that were with specific product teams.  These more focused group events are amazing.  You take a group of people who in one form or another have been working together for a while and mix them up a bit, and then give them (more...)

Oracle’s Jeff O. Henley: CFOs Should Have Much to Say on the Matter of Cloud Computing

Not that he needs me to establish his credibility…but I know for a fact that Henley has personally met with thousands of CFOs from organizations of all sizes, types, and global locales during his tenure as Oracle’s CFO, Chairman, and now Executive Vice Chairman.

In this month's Oracle Profit Magazine, Outside In, he share's his firsthand observations on how the CFO role has evolved.


Adaptive Query Optimization in Oracle 12c : Ongoing Updates

I’ve said a number of times, the process of writing articles is part of an ongoing learning experience for me. A few days ago my personal tech editor (Jonathan Lewis) asked about a statement I made in the SQL Plan Directive article. On further investigation it turned out the sentence was a complete work of fiction on my part, based on my misunderstanding of something I read in the manual, as well as the assumption that (more...)

Tumblr Joins Expanding Lineup of Social Properties Supported by Oracle Social’s SRM Platform

Big news: Tumblr is joining Oracle Social’s SRM Platform! 

Tumblr is much more than your average micro-blogging site. In today's image-focused, socially driven environment, Tumblr is gaining in importance with brands. As our partner NBC Sports noted in AdWeek, "Tumblr is a visually rich, social-friendly platform" that they found a "perfect" place for SuperBowl content. According to Tumblr, there are 251.8 million blogs publishing 80 million posts in 16 different languages (more...)

Are You Cloud Curious? Check Out Our Channel Cloud Opportunities Webcast Series

The cloud has revolutionized how organizations are building and leveraging systems and applications to run their businesses. Do you know what direction you’ll take with the cloud?

To help you navigate these new channel opportunities in the Oracle public cloud, Oracle PartnerNetwork has put together an informative webcast series for our OPN resellers, systems integrators and implementation partners. We highly recommend that you take advantage of this resource to elevate your business with Oracle Cloud (more...)

Improve SQL Query Performance by Using Bind Variables

The Securing Account Details story in the previous blog post highlighted two problems with SQL that uses literals instead of bind variables: decreased performance and security holes. In this post we'll investigate the impact on execution times in more detail. 

Why do bind variables matter for performance?

Before Oracle runs a SQL statement it checks it's valid and determines how to access the tables and join them together. This is called parsing. The optimizer (more...)