Oracle ANSI SQL and the WITH syntax

, ,

SQL language has been around for so long, that some people feel it never changes. This is obviously not true – SQL is a dynamic language that changes all the time: some changes come from the vendors themselves but often this is the result of the standard changing and Oracle adopting the new standard in a later version.

Let’s start with a short history lesson. As we all know, SQL is not a unique language for Oracle. It’s a common language with standards set by ANSI. The first version of the language standardization was presented back in 1986 with the issuance of SQL86. In 1992, a revised version of the language came out (SQL-92). When Oracle tried to implement this standard at full, they noticed that some of the things there are really different from how Oracle did things so it adopted only a part of the standard in Oracle RDBMS 8 (and 8i).
Read more

hadoop logo

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.

Read more

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).

Read more

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.

Read more

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).
Read more

Welcome to my “new” blog

Welcome to my new (re-new) blog.

This blog was started 4 years ago in Hebrew and on the 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 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!