Ch.02-23 Dimension Types: Slowly changing dimension SCD 0,1,2,3,4 | Data Modeling | DWH Architecture

[@alm3tasem]

@9:41 في النوع الرابع، جدول الهيستروي بيشتمل على كل القيم القدمية بالاضافة للقيمة الحالية، أم القيم القديمة فقط، ويتم تسجيل القيمة الحالية في الجدول الأساسي

[@GarageEducation]

It depends on the target and the DWH tool and design. In some organizations, they separate the historical from the current snapshot in separate tables. In this case, they could think about why do we need to duplicate the records from current twice? They could stick to the definition of mini-dimension in this case. In other organizations, they keep all (historical + snapshot) the reason here (the use case) could be when we do analysis and need to join SCD with fact tables for analysis. We don't need to join with two tables to get all the data. For example, I need to get the customer location history and join with the fact of usage; in this case, I need to join with historical table and snapshot table; however, in case we add all in the hist, it will be on join. Honestly, in DWH, I saw the first part, and in Big data, I saw the second. Maybe I will add a note for this point in the additional articles reading. Please let me know if there you need any further clarification.

[@alm3tasem]

@@GarageEducation Thanks a lot for this clarification, now SCD type 4 is clear enough for me.

[@yasserhossam8943]

Extremely helpful video and great explanation, Thank you for providing that high quality content

[@GarageEducation]

Glad it was helpful!

[@amalselim7290]

Great tutorial .. thanks

[@GarageEducation]

Every video has its own link in the description to make it easy for the audience

[@amalselim7290]

@@GarageEducation Honestly Gzakom Allah kol 5eer

[@gomaa9141]

what about the shrunken rollup dimension that was mentioned at the end of the direct previous video?

[@GarageEducation]

We will publish this video today ISA

[@mostafamans4523]

كده ايه الفرق بين اول نوع وتانى نوع ال هو type 1 و type 2

[@gomaa9141]

further reading?

[@GarageEducation]

حضرتك في موقع مخصوص شغالين عليه هنرفع فيه كل حاجة إسمحلي يوم او يومين ومنحط كل حاجة

[@GarageEducation]

Kindly find this initial draft and we will update it within today and tomorrow. So, please keep checking this this page. gability.com/en/courses/big-data-in-depth/02-dwh/03-architecture/10-data-modeling/02-dimensional-modeling-further-reading/

[@amalselim7290]

Link not working

[@GarageEducation]

Please check this link.gability.com/en/courses/big-data-in-depth/02-dwh/03-architecture/ Each video has its own further readings

[@GarageEducation]

Even dimension has separated page gability.com/en/courses/big-data-in-depth/02-dwh/03-architecture/10-data-modeling/