Dropping constraint… what about the index?

In a recent release that I’ve been working on, we had to drop and recreate some of the unique/primary key constraints (due to columns being added into the constraint) on some of our tables.

Prior to working in this team, I had only ever come across explicitly creating the indexes for a table, similar to:

create table test_explicit_index (col1 number,
                                  col2 varchar2(30),
                                  col3 date);

create unique index col1_exp_pk on test_explicit_index (col1);

We can see the (more...)

Moving from PeopleSoft to the Oracle Cloud

Those of you who know me will know that I’m working at Cedar and we’re moving from PeopleSoft to the Oracle Cloud. I won’t talk about the company’s journey, but more how I’ve found the transition personally.

In brief, there’s a lot to learn.

Data Model knowledge

In the PeopleSoft world, once you know the table structures you could work significantly faster. Whether you were writing an SQR, an App Engine, an XMLP report, a (more...)

Oracle Audit Control part 3 – OS files

Just realized that I wrote a follow-up to Part 2 2 years ago and never posted it! So here’s the stripped-out key facts to round off auditing control a bit more:

Deleting O/S audit files is, like, totally necessary. In Oracle 12C (12.1), they are created by default as AUDIT_SYS_OPERATIONS defaults to TRUE now, so you are going to be filling up your AUDIT_FILE_DEST whether you realized it or not.

[NOTE: In theory, this (more...)

A cool thing with EXCHANGE PARTITION (part 1)

“Common sense” would tell us that if I am running a query against a table, and then all of a sudden I rip out a giant chunk of that table with a DDL command, then either

  • the query should crash, or
  • the DDL command should not be permitted to run.

But in fact, with Oracle, we can even go one better in many situations.  We can allow the DDL and still have the query (more...)

Hints

Oracle cost-based optimizer (CBO) is great, but sometimes it’s making wrong choices even when correct inputs are fed to it. In such cases, you need a tool to override CBOs choices, and one of the most popular tools is optimizer hints. The main reason they’re so popular is that they allow “quick-and-dirty” kind of fixes for performance issues (provided that query text can be altered). Other ways may be more reliable, but generally require more (more...)

Those pesky dates as strings

You might be thinking “Nothing is more frustrating that encountering a string column that is full of dates”.

But there is something worse than that…and that is, when that string column is full of potential dates, and your job is to sift out the good data from the bad data. For example, if your table looks like this:


SQL> select * from T;

DATE_STR
--------------------
qwe
01/01/2000
31/02/2000
12-jan-14
20001212
Jan 14, 2016

6 rows  (more...)

Understanding query slowness after platform change

We are moving a production database from 10.2 Oracle on HP-UX 64 bit Itanium to 11.2 Oracle on Linux on 64 bit Intel x86. So, we are upgrading the database software from 10.2 to 11.2. We are also changing endianness from Itanium’s byte order to that of Intel’s x86-64 processors. Also, my tests have shown that the new processors are about twice as fast as the older Itanium CPUs.

Two SQL (more...)

Last week in Stream Processing & Analytics 5/9/2016

This is the 13th installment of my blog series around Stream Processing and Analytics.

Last week the new release of Oracle Stream Explorer has been release, now under a new name Oracle Stream Analytics. I have written my own blog article about it. This new version is an impressive release with over 15 new major features! It really deserves the name change. Oracle Stream Analytics simplifies stream processing and enables Self Service Streaming Analytics applications (more...)

Oracle Forms Extreme Mobile Makeover Contest

 

WebSite_main_image

In today’s world, where everything is at the tip of your fingers, why are your enterprise systems glued to your office desk?  Imagine if you could access and operate your Oracle Forms/EBS systems from any location.  What if your Oracle Forms system was so agile, so easy to adapt, that any business function you do in Oracle Forms could be included in a mobile application? What would you include in your mobile (more...)

Comparing Common Queries Between Test and Production

The developers complained that their test database was so much slower than production that they could not use it to really test whether their batch processes would run fast enough when migrated to production. They did not give me any particular queries to check. Instead they said that the system was generally too slow. So, I went through a process to find SQL statements that they had run in test and that normally run in production (more...)

Evolution of Masking Vendors

Screen Shot 2016-04-22 at 12.47.52 PM

Masking with Delphix (where duplicate blocks are shared making a new copy almost free storage wise and almost instantaneous) has 4 big advantages

  1. Instant data, no copying
  2. Ease of Use
  3. Consistent across data centers and databases vendors
  4. Master/Slave

Virtual Data Masking

Delphix masking and virtualization is the most advanced solution in the market place, because Delphix doesn’t provision data. Instead of provisioning data, Delphix sets up pointers back to existing data for a new clone. When that (more...)

Workarounds

It’s been forever since I last shared any of my performance troubleshooting experiences at work. This week, I got a case that I think is worth publishing, and I decided to write about it in my blog. So, here we go…

A few days ago, I received a complaint about unstable performance of one of frequently running SQL reports on a 11gR2 database. Most of the time it completed within a couple of minutes, however, on (more...)

Fishbowl Hackathon 2016 Summary – Oracle WebCenter Innovations with Slack, Google Vision, and Email

This post comes from Fishbowl’s president, Tim Gruidl. One of Tim’s biggest passions is technology innovation, and not only does he encourage others to innovate, he participates and helps drive this where he can. Tim likes to say “we innovate to help customers dominate”. Tim summarizes Fishbowl’s Hackathon event, held last Friday and Saturday at Fishbowl Solutions, in the post below.

TimWhat an event! I want to start by thanking Andy Weaver and John Sim (Oracle (more...)

Delphix Replication

Someone just asked on the Delphix Forums whether they could test Delphix replication with the free version of Delphix called Delphix Express.

I’d never tried, so I sat down to try and was amazed at how easy it was.

I created twoDelphix Express installations.

On one engine, the source engine, (http://172.16.103.16/)  I linked to an Oracle 11.1.0.7 database on Solaris Sparc called “yesky”.

On that same engine I (more...)

Jonathan Lewis

I am finally getting around to finishing my four-part blog series on people who have had the most influence on my Oracle performance tuning work. The previous three people were Craig ShallahamerDon Burleson, and Cary Millsap. The last person is Jonathan Lewis. These four people, listed and blogged about in chronological order, had the most influence on my understanding of how to do Oracle database performance tuning. There are many other great (more...)

java.lang nullpointerexception While Installing 12.1.0.2 RAC Database Software

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I have an Oracle  12.1.0.2c cluster having following 5 nodes :

  • Hub Nodes : host01, host02, host03
  • Leaf nodes: host04 and host05

I wanted to install RAC database software on the 3 hub nodes i.e. host01, host02 and host03.

I invoked the OUI as oracle user (Owner of Database Home)

[oracle@host01 database_12_1_0_2]$ ./runInstaller

and chose the option to install RAC database software only on the 3 hub nodes.

After (more...)

Partially Applied Functions in JavaScript

First of all, what are partially applied functions? There’s a little bit of theory here. The concept of partially applying functions stems from the functional way of programming. There it’s tightly linked with a concept called currying. Currying says that every function can be written as a function with only one parameter. By currying and un-currying you can achieve this goal. If this sounds very hard and complex, do not fear, in essence it’s quite (more...)

Collaborate 2016 Oaktable World Sessions

Oaktable World Las Vegas is happening at Collaborate 2016! Many thanks to Tim Gorman, Alex Gorbachev and Mark Farnham for organizing!
Free Oaktable World t-shirts available at Delphix booth 1613 on Tuesday and at the Oaktable World talks on Wednesday. Also available at the Delphix booth is free copies of Mike Swing’s “the little r12.2.5 upgrade essentials for managers and tema members”. Mike will be doing Q&A at the Delphix booth Tuesday 1:15-2:00 and book (more...)

Inflexible Security (MailChimp fail)

Maybe I shouldn’t have written about flexible security, because I immediately starting hitting inflexible security, locking me out.

Today’s fail is courtesy of MailChimp.com, which I use for my newsletters. It’s OK that they decided they want a confirmation when I log on to my account from India, but it is not OK that they require a text message passcode with no other option.

I have my phone in flight mode, because I don’t (more...)

Log file parallel write wait graph

I got a chance to use my onewait Python based graph to help with a performance problem. I’m looking at slow write time from the log writer on Thursday mornings. Here is the graph with the database name erased:

log_file_parallel_write_waits

We are still trying to track down the source of the problem but there seems to be a backup on another system that runs at times that correspond to the spike in log file parallel write (more...)