Posts

ilOUG Oracle Technologies Meetup Group

,

I have a confession: I love Oracle User Groups. Here. I said it.
I think that the idea of a community gathered around common professional interests and expertise are great. It’s an opportunity to meet you colleague and learn a thing or two you don’t get to work with on a daily basis from your peers. For junior DBAs it’s even more important. They have the opportunity to look into their future and see where they want to be when they get more experienced. In my opinion, networking is SUPER important!

tl;dr: ilOUG is reinstating the quarterly SIG meetings, I’m one of the organizers, join us if you’re in Israel!

https://www.meetup.com/ilOUG-Oracle-Technologies-Meetup

For the longer version, read bellow… 🙂

Read more

Fixing PRVF-0002 : Could not retrieve local nodename

Here is a common question I get from junior DBAs (and operating system who tries to help by installing the Oracle Home themselves). The question sometimes sounds like this: “After we installed the new database server and changed its hostname, we try to install the Oracle Home using the runInstaller but hitting the following error: PRVF-0002: Could not retrieve local nodename. How do we resolve it?”.

In terms of looks, the error message looks something like this (this is from Oracle 11g, but it also happens in other versions as well):
prvf-0002

Indeed, a problem – but what can it be?
Read more

Using Read Only Tables

,

While visiting a customer, we had a conversation about the correct way to stop users from writing to code tables. The customer described his ancient logic: when he wanted to move table to a read only state, he removed the write (insert/update/delete) permissions from all of his users. That was good enough for him for years – since he started using this method way back in Oracle 8. All was well, util this week he found out that the table owner’s privileges could not be revoked – and due to a bug, someone accidentally deleted the table content…

So I asked him why didn’t they change it to read only tables and he had no idea what I am talking about.
Well, I wrote about read only table like 6 years ago (in Hebrew), but I never thought I should translate it – since it’s a fairly “old” (11gR1) feature and everybody knows about it, right?
Well, this week proved me wrong. Here is what I wrote about it years ago.

Read more

Fixing Dataguard Wrong File Location Problem

When we add a new datafile to the primary environment of a dataguard setup, we need to add the datafile to the standby environment as well if we want the manged recover to continue working. We can do that manually if we want – but fortunately for us Oracle comes with a built in feature for automatically creating the file in the standby as well. All we need to do to set it up is to set the parameter “standby_file_management” to AUTO and create a conversion map for the files location using DB_FILE_NAME_CONVERT parameter.

All of this should be running well, until some Junior DBA (hey D., you know I’m talking about you.. 🙂 ) decides to create a new datafile in the non-default location.
Once that happens, the dataguard is unable to create the new datafile and the managed recovery will stop working.

This is a short guide I created years ago for how to identify and solve the problem.

Read more

Presentations-Presentations-Presentations

, ,

For the last few months I’ve been presenting a lot in various venues. I presented in Oracle Open World, HROUG conference in Croatia, DOAG in Germany, Oracle Week in Israel (3 day long presentations!), MySQL User Group in Israel and in some more private conferences and private events. I was also accepted to IOUG collaborate in Las Vegas in April and I’m planning to give some Webinars soon.

I believe that educating and sharing is pretty important, and since most of my presentations are in English (the slides, but sometimes also the session itself) – I usually keep the habit of uploading it to my SlideShare for people to enjoy it.

I was talking to a customer-friend yesterday, and he told me that he’s been reading my blog for a very long time, but he’s kind of sad he can’t see all my decks there. So, I’m taking his advise and for the next few days, I’ll post all of my presentations here – a post for each of the presentations and will add the demo scripts, wherever applicable.

Feel free to ask questions and make requests – I’d love to hear you opinion and suggestions!

All of the presentation are available for download from Slideshare.
My SlideShare link: http://www.slideshare.net/zohare.

Zohar

plumber

Using External Table on Windows RAC ACFS

One of my customer is using Oracle RAC (11.2.0.3) on Windows 2012. This is might not be the most ideal setup I’ve ever seen, but it works and we’ll leave it by that.

One of the side effects of using Oracle RAC on Windows is that some of the basic things I am used to do when using RAC on Linux (for example) is behaving differently when it comes to windows. Here is a quick example for that.

I was asked by the customer to create an external table using a fixed-record file. This should be easy enough, right? Well, yeah – but we need to consider that we might connect to the database from either node so we need to put the file on a shared storage.

The customer is using ASM for his RAC so what better solution we have than using ACFS configured on top of the ASM?

Read more