Before reading this article, you should have a good understanding of single joins between two tables and be clear on the differences between inner and outer joins. Check out my previous post A Primer on Joins to help you accomplish this. Have you … Continue Reading
Peter is a consultant specializing in the design and development of database systems using SQL Server and .Net technologies. Peter has operated a nation-wide consulting business since 1991. He was a course designer and instructor of database and software development technologies at Harvard University; UC Berkeley, and the Worcester Polytechnic Institute, and he is author of “An Intuitive Approach to Database Design; An Introduction to Data Modeling.”
Peter uses an intuitive approach to learning that applies the way we all learn in the real world and gives students experiences on which to draw when they’re back on the job applying their new skills.
“People love to learn,” Peter says. “Learning is what we do. We’re good at it. It’s fun! Sometimes we learn by being told how something works, other times we observe others doing things; but learning is the most fun, satisfying, and enduring when we have our own empirical learning experiences—our own AHA! moment when we experience a discovery. The classroom offers a great opportunity to create those moments in a fun and focused environment. It is very rewarding to me when a student tells me afterward that the experience they had in the classroom is what allowed them to finally understand a topic and solve a tough problem at work.”
The golden rule of OLTP database design is that every table should represent one, and only one, entity-type. Without this rule, databases can exhibit three data anomalies (insertion, deletion, and update anomalies) that undermine data integrity. But adherence to the … Continue Reading
As we see in the SQL 100 and SQL 250 courses, and as we further explore in this article, joins are used in queries that need to access data stored in more than one table (served up either by the … Continue Reading