Should You Use An ETL Tool?

The Extract, Transformation, and Load (ETL) system is the most time-consuming and expensive part of building a data warehouse and delivering business intelligence to your user community. A decade ago the majority of ETL systems were hand crafted, but the market for ETL software has steadily grown and the majority of practitioners now use ETL tools in place of hand-coded systems. Does it make sense to hand-code an ETL system in 2008, or is an ETL tool a better choice? Kimball Group now generally recommends using an ETL tool, but a custom-built approach can still makes sense. This article summarizes the advantages and disadvantages...

k-means Clustering

k-means clustering is a data mining/machine learning algorithm used to cluster observations into groups of related observations without any prior knowledge of those relationships. The k-means algorithm is one of the simplest clustering techniques and it is commonly used in medical imaging, biometrics and related fields. The k-means Algorithm The k-means algorithm is an evolutionary algorithm that gains its name from its method of operation. The algorithm clusters observations into k groups, where k is provided as an input parameter. It then assigns each observation to clusters based upon the observation’s proximity to the...

Kimball University: Industry Standard Data Models Fall Short

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 model design effort. Every manufacturer takes orders and ships products to fulfill the orders. Every insurance company sells policies and processes claims. Every transportation company moves cargo between an origin and a destination. The list goes on across other industries. Why...