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Introduction to Big Data, Hadoop and NoSQL

In the last few weeks I participated in the training of a DBA course in John Bryce education center in Israel.

The course is titled “Master DBA” – it’s an 8 month evening course to train new DBAs from head to tail. It’s divided into two parts; the first part is about SQL, PL/SQL, and OU “Oracle Database Administration Workshop” parts 1 and 2. The students are then encouraged to take the OCA and OCP certification exams. After finishing this part, the students learn Linux, scripting and other IT skills a DBA should have.

In the second half of the course, the students learn about Big Data (mostly Hadoop), Python (as a programming language) and NoSQL (MongoDB or CouchBase, not really sure).

Yesterday I gave a class about the introduction to Big Data, Hadoop, and NoSQL.

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Installing Oracle – Part 2: Creating an Instance

In the earlier post we installed the Oracle version (software only) but still didn’t create a database instance. In this post we will go over an installation procedure of a basic CDB database instance. This will be the first instance on that database server (and I’ll explain later why this is important).

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Installing Oracle – Part 1

It’s been a few months since came out. Here is a basic guide for installing Oracle 12c (
This is a two-part post – in the first part we will install the software and in the next part we’ll go over creating the new database instance.

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Database In Memory presentation from the ilOUG SIG meeting

A few weeks ago, I was invited to give a lecture at the Israeli user group meeting (ilOUG DBA SIG). The presentation topic was the new Oracle 12c feature – the Database In Memory (aka In Memory Option).
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Welcome to my “new” blog

Welcome to my new (re-new) blog.

This blog was started 4 years ago in Hebrew and on the wordpress.com platform where it was simply called “The Zohar Elkayam blog”. In those last 4 years I’ve written dozens of articles which I felt will be useful to my forgetful me and to my readers who came along for the ride.

Lately I realized that wordpress.com has its limitations and I felt that I really need to move on to a new hosting platform. I figured out that by writing in only one language (Hebrew), I am missing most of my potential audience so I created this new bi-lingual blog, on a self-hosted platform with a new interface.

My goal is to have most of my old articles translated and connected to each other so people could read them in the language they prefer. I will also publish my new articles in both English and Hebrew at the same time.

I will work on translating most of my old posts (the ones that are still relevant) in the near future.

Feel free to reach out and contact me – if you have any questions or comments.

Have a great day!


How to transparent transition to the DR with few easy steps

I was asked by one of my readers about “transparent transition” between the Primary and Standby databases when using a Data Guard environment. The question sounded relatively simple: how do you configure the clients so it will automatically work with the active site at any point in time?

The truth is that the solution is a lot easier than what you might think, and I even got to implement it in on an Oracle 10g database, more than five years.

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