In this article, I am going to explain to you what are Gregorian and ISO Calendar?

ISO 8601 Calendar

The week numbering was reintroduced by ISO in June 1988 to solve the problem that each week in a year should have seven days even for the first and last week…


Connecting and querying AWS redshift from python is similar to connect with the other relational databases.

In this article, we will use sqlalchemy,psycopg2, and pandas libraries to import the redshift data into pandas Dataframe.

if these libraries are not installed in your system then you need to install them via…


We usually heard the term 'null' when we work with data so what does it mean?

It looks similar to blank or 0 but actually, it is not. Null is a reserved keyword in SQL to represent missing values in the database. Operations on the missing values will always be…


S3 is the simple storage service offered by AWS. used to store the objects through a web service interface.

Widely used file storage service for the creation of data lake or storing raw data.

Redshift is a cloud database service offered by AWS for designing data warehouse(DWH) solutions.

When we…


Let’s continue from my last blog ( https://ayushbi.medium.com/slowly-changing-dimensions-and-its-type-1-implementation-is-redshift-with-a-column-with-an-2f8eb92d4842 ) on SCD’s where we have seen the different types of SCD, Identity clause, Surrogate keys, and Implementation of Type 1 in redshift.

Redshift Implementation of SCD type 2

We know that Type-2 of SCD stores the history in the Dimension table…


In Datawarehousing we usually come across a type of dimension called as slowly changing dimension (SCD). In this article, we will go through the SCD and its implementation in redshift with the help of the identity column.

Before begins the implementation of SCD type1 let’s try to find out the…


Why do we need materialized views in amazon redshift?

In data warehousing, Sometimes you need to query a very large table or the combination of multiple tables like a fact and multiple dim across it for getting the desired aggregated output. …


Recently tableau has released the Tableau 2020.4 beta with some cool features.

Please find them below tableau desktop cool features:-

1:- Multi Marks layer

Now it’s quite easy to add layers on maps so that we can compare different marks on a single tableau worksheet.

2:- Redshift spatial data support


Definition from Kimball:- A junk dimension is the combination of several row-level cardinality flags and attributes into a single dimension table rather than modeling them as a separate dimension table.

Why do we need to create a junk dimension?

When we start to model a data warehouse, frequently we come…

Road2Data

A data enthusiast, Having 8 years of experience in Data Warehousing and Business Intelligence field, Currently working as Senior BI developer at Home24 Berlin.

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