Kimball Dimensional Modeling Practices Waterfall Only?

Kimball Dimensional Modeling theory and practices are the most widely accepted processes for consolidating data from different sources into a central “Delivery Area” for consolidated cross functional reporting. Or simply a process for normalizing and standardizing data from several data marts into a data warehouse for Business Intelligence (BI) reporting.

From “The Data Warehouse Tool Kit”; Second Edition; Kimball, Ross; 2002; John Wiley and Sons, Inc.; Page 22:

Finally, dimensional models are gracefully extensible to accommodate change. The predictable framework of a dimensional model withstands unexpected changes in user behavior. Every dimension is equivalent; all dimensions are symmetrically equal entry points into the fact table. The logical model has no built-in bias regarding expected query patterns. There are no preferences for the business questions we’ll ask this month versus the questions we’ll ask next month. We certainly don’t want to adjust our schemas if business users come up with new ways to analyze the business.

The main tool used to discover the applicable Dimensions for a model is the Business Process Dimensions Matrix, see Figure 1. Each row represents a Business Process and Each Column a Dimension available within the Delivery Area that is populated manually or through the consolidation of the source data.


Figure 1. Kimball, Ross; et al.; Page 79.

On this surface this looks like a Waterfall approach… Identifying all the requirements upfront before development starts. I disagree. This document should be an organic repository that is constantly updated with changes like new Dimensions or Business process as additional data sources are added to the system. Further, I believe this matrix is the perfect primer for authoring User Stories. For Instance the first Business Process would translate to:

As an Inbound Contact Center Supervisor I want to see Voice, Chat, Email and Fax metrics summarized by Date, Time, Agents (Users), Goals and Locations So that I can…

The last section of the User Story where the reason or benefit is recorded also derive from a central tenant of BI practices. That central tenant is, “Every report must answer a question to aid in the conclusion of one or more business decisions.” The question we’re answering does not show up on the matrix, but should be part of the BI project management artifacts and the User story is the perfect place to record it.

If you’re reading this you may be a BI solution developer and suffered the frustrations of pointless and repetitive presentations (reports and dashboards) because your customers don’t know what they want. Someone on the project must take it upon themselves to get the stake holders to commit to the questions they want to answer. In Agile Scrum, it would make sense that the Product Owner maintains the matrix and the user stories and therefore should be responsible for those commitments. Here’s an Example of the resulting user story.

As an Inbound Contact Center Supervisor I want to see Voice, Chat, Email and Fax metrics summarized by Date, Time, Agents (Users), Goals and Locations So that I can more accurately forecast future staffing needs.

The wide acceptance of Kimball practices predates the wide acceptance of Agile Iterative Development practices. Therefore, several professionals in the space are unwilling to adapt their practice of Kimball methodologies. Hopefully this discussion will aid in efforts to convince these BI resources to modify their approach to conform to the Software Development Life Cycle (SDLC) methodology the rest of the development team uses.


Job Req. Sanity Check

Let me start by saying I am not an HR guy. Nor have I ever been a full-time recruiter of any sort. So perhaps, I’m way off base with my thoughts on this topic. PLEASE straighten me out if I am because there are a lot of practices within this space that make no sense to me.

I.  The Skill Set Years Experience Mismatch

Lately I have seen a flood of open position postings on the various job boards that will say something to the effect of “Jr. Developer\Recent College Grad\1-2 Years experience” as the headline of the posting. Only to find in the requirements section, experience (which to me means more than just exposure or reading a help doc online) for some 30 different technologies. Maybe, yes maybe with the right set of circumstances a Jr. resource as described in the headline might have started in an environment where he or she was given free rein to provide solutions through whatever means. I was lucky enough to have started my career as the only software developer for a successful Insurance company where I was able to explore whatever new technology came along and experiment with different techniques. I think this is pretty rare. Some companies spend the first 6 months breathing over a new resources shoulder with weekly code reviews before they’re promoted to level on and the code reviews come when the developer is ready. Many companies only let their resources sustain existing code and teach them just the basics to troubleshoot the existing technologies while the more senior staff works on innovation.

So are the hiring managers or recruiters looking for 80% of the required skills? One or two? Software design and development professionals are detail oriented and precise personalities. If I can’t talk about every skill listed, I’m not going to apply for a position.

II.   Competing Technologies

Another favorite of mine is when the laundry list of experience includes market competitors. The posting is looking for someone with 5 years experience and expert knowledge of Oracle, DB2 and SQL Server, or Expert level .NET and Java. First, can you really become expert in 5 years, especially if the maybe 2 of those you were just doing maintenance work (i.e. spell checking websites)? Secondly how many companies invest tens of thousands of dollars in SQL Server and more tens of thousands on Oracle? As a vendor software developer your product may need to support more than one database platform. However, what percentage of the candidates the job market hail from vendor software companies? Are there really any transferrable skills between .NET and Java? It seems to me trying to grow one resource into an expert of both is far more expense than cultivating two specialists and most companies would do the latter.

These types or requirements lead to a lot of confusion for candidates. They don’t know if they should bother applying or not. The recruiters are inundated with resumes that don’t fit the request from the hiring customer.

III.   Automated Recruitment Phone Recruiting

This year in particular I have been flooded with outsourced call center recruiter calls. These calls always follow the same format.

  • I answer the phone to silence
  • A few seconds later someone in a very thick accent says, “Hello may I speak to George?”
  • “Yes this is George.”
  • Faster than any normal human being should be able to speak -“Uh hi. My name is gibberish. gibberish gibberish gibberish gibberish gibberish gibberish gibberish gibberish gibberish gibberish gibberish gibberish …”
  • Me, “Whatever you’re talking about I’m not interested. Thanks.”
  • Hang up.

It’s as bad as the campaign calls around supper time during an election cycle. Who in their right mind thinks this is in any way an effective means to find a qualified candidate? I seriously doubt these individuals understand the technical requirements well enough to successfully phone screen much less are able to fight through the language barrier well enough to have a real conversation about the candidate or the opportunity.

IV.   Don’t Read the Resume

Another new interesting fishing tactic is the mail blast, or I guess that’s what’s going on. Why else am I getting emails for Jr. or Intermediate 5 years or less positions from the job boards where my resume clearly showing 16 years of experience are posted? Or the expert Java Architect roles I was sent when Java J2EE doesn’t appear anywhere on my resume? Recruiters, does this tactic work?

I understand there is a perception in the US job market right now that a lot of people are out of work and some companies are hoping to cash in on getting better qualified candidates for less compensation. This perception has created a recruiter feeding frenzy atmosphere. The truth is most of the top ranked talent is aware of what’s going on and they’re sitting this cycle out, or contracting. The unemployment rate among software development professionals is not nearly as high as other skill sets like manufacturing and construction. I believe this tactics will not be successful, and my land your corporation with a lot of negative feedback on a site like

Work Yourself Out of a Job

Has anyone in your management structure ever told you that if they could just clone you 4 or 5 times the company would be worry free? That is great feedback. You have earned yourself many years of job security. In fact you might say you’ve made yourself so indispensable at your current position, you’ll never be able to grow out of it.


For a lot of professionals in the world that’s exactly the position they want to be in. Joe is the best administrator BigCo Corp has ever had. No issues with any of the servers under his care. His management gets a little nervous when he takes a vacation because there is no one else who can do what he does the way he does it. Management doesn’t want to add any new variables to the mix and Joe will never be burdened with management training, team building, Agile methodology, mentoring, or other distractions. Likewise, Joe isn’t really all that motivated to share his expertise, both because he doesn’t like trying to explain what he does to others, and because he’s worried about losing some of his organizational expertise currency.


If you’re like Joe, read no further, because we’re going to talk about Sally. Sally, another administrator at BigCo Corp, likes having uninterrupted vacations. She has back filled her own position by training a few of her colleagues to do support her when she needs a break. Sally has taken the time to create process and systems documentation and publish it where others can reference it. Management notices that Sally can take care of her normal duties and build a team to add more redundancies to the processes. Management decides to send Sally to team building and management training. Sally becomes Joe’s new boss.


More than once in my career I worked really work and waited for my supervisors to recognize my talent and give me that promotion to management. I gotten the “Clone you” comment many times and sat on it. It took some advice for a mentor to open my eyes to the power of creating your own opportunities. You may not be able to personally improve the company’s bottom line and create more revenue that results in more growth and upward movement opportunities. If you do a great job, create a backfill for yourself and haven’t made yourself a pariah in your organizations politics, there’s a great chance you’ll get top consideration when an opportunity does show up.