SCD (Slowly Changing Dimension) is a very important concept in ETL and Data Warehouse in general.

“Slowly Changing Dimension (SCD) is a dimension that stores and manages both current and historical data over time in a data warehouse”
-Oracle

This methodology is used to track changes in the dimensions that change slowly over time.

Note: you can also read the article and more from my blog from this link

Let’s have an example:

If a customer in a bank has an account and the balance is changing every business day and this is the normal case that does not need…


Everyday we hear about the revolution of AI and computers that are gonna replace our jobs and how many jobs will disappear in our days.

Artificial Intelligence, Machine Learning, Deep Learning are going to replace our jobs in the next days but it does not yet.
It started since the 18th century when the industrial revolution began that Europe and US began to transit from hand production methods to machines.
That meant that machines replaced many jobs at this time and everyday till now the world is losing a job that can be replaced by a machine.

Nowadays there are…


Hello ETL Developers,
Today I am going to explain different ways to join or merge data sources using Informatica PowerCenter.

First way is an obvious way that is using Joiner Transformation:

Employees table and Departments table are joined using Join transformation

Joiner Transformation combines 2 sources have a common column or a Primary key-Foreign key relationship.

Muhammad Salah El-Okda

Software Engineer interested in software technologies.

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