When is a "hierarchy" not a hierarchy

Post Reply
lotsaram
MVP
Posts: 3126
Joined: Fri Mar 13, 2009 11:14 am
OLAP Product: TableManager1
Version: PA 2.0.x
Excel Version: Office 365
Location: Switzerland

When is a "hierarchy" not a hierarchy

Post by lotsaram » Wed Oct 03, 2018 12:36 pm

OK so this has been bothering me for a while.

When discussing dimension structure (particularly with other “oldschoolers”) the term hierarchy is often (mis)-used to describe internal ancestor-grandparent-parent-child relationships as opposed to the "textbook definition" of a dimension hierarchy in the context of Planning Analytics.

Dimensions having named hierarchies, and elements and their structure belonging to the hierarchies and not to dimensions is a new paradigm for most of us but the point that the term “hierarchy” now has a very specific meaning and we should use it correctly, otherwise it is confusing and we have to second guess what is actually meant.

Incidentally there's a good blog post on this topic here. I like the idea of using the term "rollup" or "rollup structure" in place of "hierarchy" to describe internal element relationship structure and basically swapping out "hierarchy" for where we would have said "dimension" in the past in pre-Planning Analytics days.

Now I may be a pedant, but I'm not that much of a pedant that I would ever insist that a business user should abide by the terminology described in the article. After all why would a business user even care? But a TM1 / Planning Analytics consultant as a subject matter expert should care. It's our job as technical experts to communicate clearly and unambiguously and using the term hierarchy incorrectly is a habit we should kick, even if it takes a little bit of effort.

Now I'll admin that this topic doesn't posses the theoretical gravitas or passions of the "single continuous vs. multiple discrete time dimensions" discussion. But anyone want to pass the popcorn and nachos?
Please place all requests for help in a public thread. I will not answer PMs requesting assistance.

User avatar
PavoGa
Community Contributor
Posts: 239
Joined: Thu Apr 18, 2013 6:59 pm
OLAP Product: TM1
Version: 10.2.2 FP7, PA2.0
Excel Version: 2013
Location: Cleveland, Tennessee

Re: When is a "hierarchy" not a hierarchy

Post by PavoGa » Wed Oct 03, 2018 2:01 pm

I'm with you on this one. Pretty much insist our teams adopt and use specific terminology to describe discrete items, sets of items or objects. We adopted rollup to describe what we use to call hierarchies as you described.

What we have found is a need to manage hierarchies, in terms of historical vs the current default hierarchies. We have gone the path of a primary name, a suffix and a numbered prefix and use the caption to describe.
Ty
Cleveland, TN

User avatar
macsir
Community Contributor
Posts: 548
Joined: Wed May 30, 2012 6:50 am
OLAP Product: TM1, SSAS
Version: 9.5 - 10.2
Excel Version: 97 - 2013
Contact:

Re: When is a "hierarchy" not a hierarchy

Post by macsir » Wed Oct 03, 2018 9:51 pm

I agree. It just takes time to get used to it.
Wherever we were used to saying dimension simply replace with “hierarchy“. Hierarchies contain rollups. In fact hierarchies are now the containers for elements, rollups, subsets and attributes (not dimensions, that was back then, we need to get to the now).
The term dimension should only be used when talking about cube structure. Dimensions in PA are merely a container for hierarchies.
In TM1,the answer is always yes though sometimes with a but....
http://tm1sir.blogspot.com.au/

User avatar
garry cook
MVP
Posts: 191
Joined: Thu May 22, 2008 7:45 am
OLAP Product: TM1
Version: 10.2.2 SP4
Excel Version: Various

Re: When is a "hierarchy" not a hierarchy

Post by garry cook » Thu Oct 04, 2018 8:43 am

Could not agree more, a difficult but important habit to break.

User avatar
Alan Kirk
Site Admin
Posts: 5830
Joined: Sun May 11, 2008 2:30 am
OLAP Product: TM1
Version: 9.5.2 64 bit moving to 10.2.2
Excel Version: 2010
Location: Sydney, Australia
Contact:

Re: When is a "hierarchy" not a hierarchy

Post by Alan Kirk » Sun Oct 07, 2018 1:17 am

Sigh, I'm still trying to get my users to stop saying "subsets" when they mean"consolidations" and vice versa...

To that end, I much prefer the term "consolidation" to "rollup". Why? Because for the foreseeable future there will continue to be a little button named "Rollup" which has a distinctly different functionality to an actual "everyone with security access can see it and use it" consolidation.

The other thing to bear in mind is that while it is good practice to use the right terminology with other professional TM1 admins and developers, there is the little problem of explaining this to end users who have read the TM1 User Guide (OK, "seen and dipped into"; nobody actually READS the thing) , where the definition of both hierarchies and dimensions are distinctly "old school".

Wait, what? Oh, Perspectives will be replaced by PAW and PAX, so that documentation and its screenshots of Excel 2003 will go away? Yeah, some millennium when the ease of installation and reliability of PAX comes even remotely close to that of Perspectives, maybe. But in the meantime those who hang on to 10.2.2 unto grim death or who go to PA2 sans the PAW / Pax installation train wreck will still be seeing said antiquated documentation and will be more than a tad confused when devs / admins who are using the New Authorised terminology speak to them.
"To them, equipment failure is terrifying. To me, it’s 'Tuesday.' "
-----------
Before posting, please check the documentation, the FAQ, the Search function and FOR THE LOVE OF GLUB the Request Guidelines.

ndivine
Posts: 17
Joined: Wed Feb 23, 2011 6:43 pm
OLAP Product: TM1
Version: Latest
Excel Version: 2013

Re: When is a "hierarchy" not a hierarchy

Post by ndivine » Mon Oct 08, 2018 5:38 pm

Dimension is still needed, not everything is a hierarchy. It's possible to have dimensions and no hierarchies, but you can't have hierarchies without dimensions.

lotsaram
MVP
Posts: 3126
Joined: Fri Mar 13, 2009 11:14 am
OLAP Product: TableManager1
Version: PA 2.0.x
Excel Version: Office 365
Location: Switzerland

Re: When is a "hierarchy" not a hierarchy

Post by lotsaram » Tue Oct 09, 2018 5:50 am

ndivine wrote:
Mon Oct 08, 2018 5:38 pm
Dimension is still needed, not everything is a hierarchy. It's possible to have dimensions and no hierarchies, but you can't have hierarchies without dimensions.
This is kinda the point. No it's not like that. In Planing Analytics all dimensions have hierarchies. You can't in fact have a dimension without a hierarchy. Many dimensions may have only ONE hierarchy and the hierarchy may have the same name as the dimension, but it's still a hierarchy all the same
Please place all requests for help in a public thread. I will not answer PMs requesting assistance.

ndivine
Posts: 17
Joined: Wed Feb 23, 2011 6:43 pm
OLAP Product: TM1
Version: Latest
Excel Version: 2013

Re: When is a "hierarchy" not a hierarchy

Post by ndivine » Tue Oct 09, 2018 4:50 pm

lotsaram wrote:
Tue Oct 09, 2018 5:50 am
ndivine wrote:
Mon Oct 08, 2018 5:38 pm
Dimension is still needed, not everything is a hierarchy. It's possible to have dimensions and no hierarchies, but you can't have hierarchies without dimensions.
This is kinda the point. No it's not like that. In Planing Analytics all dimensions have hierarchies. You can't in fact have a dimension without a hierarchy. Many dimensions may have only ONE hierarchy and the hierarchy may have the same name as the dimension, but it's still a hierarchy all the same
Yes, I guess I was thinking old UI's where the same-named hierarchy is pretty well hidden. Part of my point was the necessity of the ongoing use of dimension as a word/term; it's usage shouldn't be thrown out because it is still something uniquely different from a hierarchy.

I have clients that have upgraded to the latest versions of PA, but were not interested in using PAX/PAW for the time being, so I've stuck to old/standard terminology with them.

To your larger point, yes, I think consultants and experts should communicate as clearly as possible using correct terms (especially with each other), but when communicating with business users be flexible according to the terminology that is understandable to them while also guiding them toward the correct terminology.

User avatar
Elessar
Posts: 147
Joined: Mon Nov 21, 2011 12:33 pm
OLAP Product: TM1
Version: 10.2.2
Excel Version: 2010
Location: Russia

Re: When is a "hierarchy" not a hierarchy

Post by Elessar » Mon Oct 15, 2018 3:02 pm

Hi,

I disagree with the term "Consolidation", because this will lead to disambiguation with financial consolidation
Sorry for my English ;)

lotsaram
MVP
Posts: 3126
Joined: Fri Mar 13, 2009 11:14 am
OLAP Product: TableManager1
Version: PA 2.0.x
Excel Version: Office 365
Location: Switzerland

Re: When is a "hierarchy" not a hierarchy

Post by lotsaram » Tue Oct 16, 2018 9:32 am

Alan Kirk wrote:
Sun Oct 07, 2018 1:17 am
To that end, I much prefer the term "consolidation" to "rollup". Why? Because for the foreseeable future there will continue to be a little button named "Rollup" which has a distinctly different functionality to an actual "everyone with security access can see it and use it" consolidation.
Elessar wrote:
Mon Oct 15, 2018 3:02 pm
I disagree with the term "Consolidation", because this will lead to disambiguation with financial consolidation
I also disagree with the term "Consolidation" but not because of statutory financial consolidation. I think that is a pretty well defined term with a very specific meaning and context. Rather I disagree because "a consolidation" in TM1 already has a defined meaning referring to a (single) consolidated element that is a non-leaf element which itself has children. This is what the "C" stands for in the element type (and the ancient XDI dimension editor). I think this is therefore more rather than less ambiguous versus "Rollup".

Yes in the old subset editor there is a "Rollup" button but this refers to the action the user is performing; they are rolling up elements to form a new consolidation (or rollup). Maybe in both cases "Rollup Tree" OR "Consolidation Tree" is more descriptive and more accurate, ... but then also less simple as it requires 2 words rather than one.

Anyways, seems this topic was a less controversial than anticipated. I'm a little disappointed to be honest.
Please place all requests for help in a public thread. I will not answer PMs requesting assistance.

User avatar
Elessar
Posts: 147
Joined: Mon Nov 21, 2011 12:33 pm
OLAP Product: TM1
Version: 10.2.2
Excel Version: 2010
Location: Russia

Re: When is a "hierarchy" not a hierarchy

Post by Elessar » Tue Oct 16, 2018 10:10 am

I think it would be a good topic for the new monthly poll :)
Sorry for my English ;)

Post Reply