bforbi

 Profile Answers by bforbi Questions by bforbi

• Sep 9th, 2008

 

The primary need for establishing a parent child relationship is to form a hierarchy of the attribute elements.
Eg: Year has a child quater, quater has a child month.
In this, we can establish one-many or many to many relationships.

Eg: Year has many quarters
Quarter belongs to only one year

Hope this helps.

ucontactkumar

 Profile Answers by ucontactkumar 

• Dec 9th, 2008

 

If parent child relationship is not established it results in unwanted joins. As a result of this metric values are not retrieved properly due to improper joins. And alos it results in cross join which is deeply resource intensive and affects the performance.

Shikha Sood

• Aug 15th, 2014

 

If parent child relationshipship is not defined properly then it can throw fact level errors if fact is stored at lower level attribute and that attribute is not defined or joined by parent child relationship....

praveen

• Aug 20th, 2014

 

Purpose of maintaining parent and child relationship is to establish joins and to make sql performance good

anandvishnu2010

 Profile Answers by anandvishnu2010 Questions by anandvishnu2010

• Aug 22nd, 2015

 

Yes,
1. Defining Parent child relationship is important for proper joins between related dimensions &
2. Also it helps in creating proper (system) hierarchy.

Abhay

• Oct 19th, 2016

 

Consider Time as a Dimension. Now your data warehouse can have Facts which store data at various levels of this Time dimension. Eg: Hourly, Daily, Weekly, Monthly, Quarterly, Yearly. When you build a report that contains multiple metrics which are at different levels of Time dimension, MSTR SQL engine will not be able to bring them together if there is no relationship between different attribute levels of Time dimension. By default, MSTR creates system hierarchies, but they have limitations as they allow only top level attribute as the entry point. To make the navigation better, top to down or bottom up, it is required that you create a user hierarchy for the same and use it in your report instead of system hierarchy.