For my final Design Tip, I’m returning to a fundamental theme that’s not rocket science, but too often ignored: business-IT collaboration. If you buy into the proposition that the true measure of DW/BI success is business acceptance of the deliverables to improve their decision-making, then buying into the importance of collaboration should be easy. Achieving […]
Over the years, we’ve worked with countless exemplary DW/BI project team members: smart, skilled, dedicated, and motivated, coupled with a healthy dose of mutual trust, respect, and camaraderie with their teammates. Teams with members who possess these characteristics tend to fire on all cylinders, with the resulting whole often greater than the sum of the […]
Dimensional designs often need to accommodate multivalued dimensions. Patients can have multiple diagnoses. Students can have multiple majors. Consumers can have multiple hobbies or interests. Commercial customers can have multiple industry classifications. Employees can have multiple skills or certifications. Products can have multiple optional features. Bank accounts can have multiple customers. The multivalued dimension challenge […]
Many organizations are embracing agile development techniques for their DW/BI implementations. While we strongly concur with agile’s focus on business collaboration to deliver value via incremental initiatives, we’ve also witnessed agile’s “dark side.” Some teams get myopically focused on a narrowly-defined set of business requirements. They extract a limited amount of source data to develop […]
Ralph introduced the concept of slowly changing dimension (SCD) attributes in 1996. Dimensional modelers, in conjunction with the business’s data governance representatives, must specify the data warehouse’s response to operational attribute value changes. Most Kimball readers are familiar with the core SCD approaches: type 1 (overwrite), type 2 (add a row), and type 3 (add […]
Some clients and students lament that while they want to deliver and share consistently-defined master conformed dimensions in their data warehouse/business intelligence (DW/BI) environments, it’s “just not feasible.” They explain that they would if they could, but with senior management focused on using agile development techniques to deliver DW/BI solutions, it’s “impossible” to take the […]
Accumulating snapshots are one of the three fundamental types of fact tables. We often state that accumulating snapshot fact tables are appropriate for predictable workflows with well-established milestones. They typically have five to ten key milestone dates representing the workflow/pipeline start, completion, and the key event dates in between. Our students and clients sometimes ask […]
Industry-standard data models are an appealing concept at first blush, but they aren’t the time savers they are cracked up to be. What’s more, these prebuilt models may inhibit data warehouse project success. Vendors and proponents argue that standard, prebuilt models allow for more rapid, less risky implementations by reducing the scope of the data […]
Over the years, we’ve described common dimensional modeling mistakes, such as our October ’03 “Fistful of Flaws” article in Intelligent Enterprise magazine. And we’ve recommended dimensional modeling best practices countless times; our May ’09 “Kimball’s Ten Rules of Dimensional Modeling” article has been widely read. While we’ve identified frequently-observed errors and suggested patterns, we haven’t […]
A student in a recent Data Warehouse Lifecycle in Depth class asked me for an overview of the Kimball Lifecycle approach to share with their manager. Confident that we’d published an executive summary, I was happy to oblige. Much to my surprise, our only published Lifecycle overview was a chapter in a Toolkit book, so this Design Tip […]