SQL> alter table p_objects
2 add partition p201410
3 values less than (to_date('2014/11/01','yyyy/mm/dd'))
5 subpartition p201410_spdts values ('DTS')
Here’s a script to create a table, with index, and collect stats on it. Once I’ve collected stats I’ve checked the execution plan to discover that a hint has been ignored (for a well-known reason):
create table t2 as select mod(rownum,200) n1, mod(rownum,200) n2, rpad(rownum,180) v1 from all_objects where rownum <= 3000 ; create index t2_i1 on t2(n1); begin dbms_stats.gather_table_stats( user, 't2', method_opt => 'for all columns size 1' ); end; / explain plan for (more...)
My friend and colleague, ACE Director Brendan Tierney, has recently published the reference book Predictive Analytics Using Oracle Data Miner. It is the first comprehensive book on the subject matter. The book is primarily aimed at the Oracle Data Scientist/Data Miner. The other target audience are Oracle developers who implement the data mining models created by the Data Scientists in their applications, e.g. OBIEE. Some of the areas covered are also relevant for Oracle (more...)
One annoying thing from installing Oracle Database 11g on Fedora, was that the up arrows for command history didn’t work. I decided to fix that today after seeing Lutz Hartmann’s article on
rlwrap. Unfortunately, the
epel (Extra Packages for Enterprise Linux) package he recommended doesn’t run on Fedora 20. You can read my tale of woe, or skip to the
.bashrc function that fixed it when I installed only
Attempting it on
A couple of people have asked me recently about a classic problem that most DBAs know: how to view ASM trace files in the VIM editor when the filenames start with a + character. To my surprise, there are actually quite a few different ways of doing it. Since it’s come up, I thought I’d list a few of them here… If you have another one to add, feel free to comment. I know that (more...)
The fourth issue of OTech Magazine, the independent magazine for Oracle professionals, is available. For the summer 2014 issue there are some more personal articles included. Titles vary from The Spiritual Programmer to The Next Generation: Oracle SOA Suite 12c and back via How to protect your sensitive data using Oracle Data Vault.
Download OTech Magazine – Summer 2014 here.
It’s funny how you can make little savings in work all over the place in Oracle if you’re prepared to look a little closely at what’s going on. Here’s a quirky little example with LOBs and function calls that might just have some greater relevance in other situations. Here’s a little data set, and two queries that I might run against it:
create table tbl( c1 clob ) lob (c1) store as c_lob( disable storage (more...)
We (Gorcan, Glen, Debra and I) arrived into Mexico around 10pm and had a few minutes wait for our local user group contact to meet us. They had arranged transportation to our hotel.
The next morning (Friday) was the day of the OUG Mexico conference. We were collected from the hotel and taken to the conference venue. Our transport had to made a number of trips to/from the conference venue to cater for all the (more...)
This post is to address a failed Weblogic start in EM12c. The fix is performed on a Windows host, but the fix can easily be for any EM12c environment that experiences this issue. In the below instructions, just replace the %OMS_BASE% for Windows Env Var to $OMS_BASE for Linux/Unix.
Issue: OMS Fails to Start and Points to Weblogic Issue in EMGC_OMS1.out File.
Error in Out File: <Critical> <WebLogicServer> <BEA-000386> <Server subsystem (more...)
Before 11g if you added a new column to a table then Oracle had to lock and physically update all rows in the table. Possibly a painful process :) 11g helped with that a little, giving metadata only default values for NOT NULL columns, so the change was done only in data dictionary, not in the table data.
SQL> create table default_values ( 2 id number primary key 3 ); Table created. SQL> insert into (more...)
A recent addition to my Oracle PL/SQL library is the book Oracle PL/SQL Performance Tuning Tips & Techniques by Michael Rosenblum and Dr. Paul Dorsey.
I agree with Steven Feuerstein’s review that “if you write PL/SQL or are responsible for tuning the PL/SQL code written by someone else, this book will give you a broader, deeper set of tools with which to achieve PL/SQL success”.
In the foreword of the book, Bryn Llewellyn writes:
There are various tell-tale signs that something is not quite right with your Oracle Data Integrator implementation. Does your ODI architecture suffer from the following symptoms?
- The ETL seems to take forever
- Some data flows take more than 30 minutes
- Your developers take ages to implement new data flows or change existing mappings
- The ETL breaks at least once a week
- No meaningful and consistent set of naming standards and coding conventions has been implemented.
After the OUG Panama conference we arrived later that night in San Jose the capitol of Costa Rica. The whole emigration, luggage pick up and customs was the smoothest experiences I have ever experienced at an airport. All was done in a matter of minutes. All the booths for emigration and customs was open and staffed. When was the last time you have ever seen this before. It was a very positive start to our (more...)
Had a chat with a dear old friend this week. Middle-manager for a Fortune 500 corporation. Big Oracle customer. Lots of (more...)
I know, I know- none of you are using Microsoft Windows. This is why I get so many questions on this topic and why there is so much interest in a white paper that no one thought I needed to write. Well, while that pesky ol’ white paper is in review, I’m going to go onto a secondary topic of how to monitor a Microsoft Active/Passive cluster with Enterprise Manager 12c, release 4.
I’m sharing this in the hope of saving someone from an unwelcome surprise.
I recent upgraded an Exadata system from 22.214.171.124.1 to 126.96.36.199.1. Apart from what turns out to be a known bug that resulted in the patching of the InfiniBand switches “failing”, it all seemed to go without a snag. That’s until I decided to do some node failure testing…
Having forced a node (more...)
I’ve been struggling to find time to have any interaction with the Oracle community for the last couple of months – partly due to workload, partly due to family matters and (okay, I’ll admit it) I really did have a few days’ holiday this month. So making my comeback with a bang – here’s a quick comment about the 12cR2 in-memory feature, and how it didn’t quite live up to my expectation; but it’s also a comment (more...)