All posts by mrb_sdg_adm

About mrb_sdg_adm

Michael Blaha is a consultant and trainer who specializes in conceiving, architecting, modeling, designing, and tuning databases. He has worked with dozens of organizations around the world. Blaha has authored seven U.S. patents, seven books, many articles, and two video courses. He received his doctorate from Washington University in St. Louis and is an alumnus of GE Global Research in Schenectady, New York.

Revised ERwin model after DBRE

A Database Reverse Engineering Case Study

In a blog last year we discussed database archaeology, which is another name for database reverse engineering. Reverse engineering is the inverse to normal development. We start with an application and work backwards to understand the software and infer its content.

This month we’ll take a further look at database reverse engineering, from the perspective of a simple case study. We’ll reverse engineer the database beneath WordPress and populated with a snapshot of the data for this website. The case study illustrates mechanics and the kinds of insights that reverse engineering can provide.

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A suggestive picture for the concept of database grading.

Database Grading, Part 2: Database Models

picture by Greg via Flickr

This article is the second in a series of two blogs that present our grading scale for database quality. We assign separate grades for the quality of a database design (previous blog) and the underlying model (this blog). The design grade measures the quality of the database syntax. The model grade measures the quality of the semantic concepts underlying the database. Applications can have different design and model grades.

Continue reading Database Grading, Part 2: Database Models

A suggestive picture for the concept of database grading.

Database Grading, Part 1: Database Designs

picture by Greg via Flickr

While working on database projects, we often find ourselves doing reverse engineering. Reverse engineering is the inverse to normal development. Developers start with an application and work backwards to understand the software and infer its intent. Reverse engineering can apply to a variety of artifacts, such as hardware, programming code, and databases. Our focus here is on relational databases.

There are many reasons for database reverse engineering. One reason is to assess software quality. For example, you may want to assess the quality of a vendor product or an internal legacy application. Information systems revolve about a database, so you can use database quality as an indicator of software quality.

This article is the first in a series of two blogs that present our grading scale for database quality. We assign separate grades for the quality of a database design (this blog) and the underlying model (next blog). The design grade measures the quality of the database syntax. The model grade measures the quality of the semantic concepts underlying the database. Applications can have different design and model grades.

Continue reading Database Grading, Part 1: Database Designs

Runners as a metaphor for agile

Agile Techniques Are Helpful with Databases

picture by Kanban Tool via Flickr

I’ve been practicing agile database techniques for about twenty years now. My use of agile techniques didn’t start as an explicit plan. Rather it evolved over time as I was working on consulting projects. It made sense to look for ways of working faster and better and with greater customer interaction.

I can think of at least three kinds of agile database techniques.

  • For data modeling.
  • For data warehouse development.
  • For database reverse engineering.

Continue reading Agile Techniques Are Helpful with Databases