Practical Object-Oriented Models in SQL

Bill Karwin (Karwin Software Solutions)
Databases, Programming
Location: Ballroom A3/A6
Average rating: ****.
(4.33, 6 ratings)

SQL is from Mars, Objects are from Venus.

This talk is for software developers who know SQL but are stuck trying to implement common object-oriented structures in an SQL database.

  • Polymorphism: Suppose your blog supports comments, but then your comments need to reference multiple types of content, for example news, blog articles, and videos. What then?
  • Extensibility: We’ve all designed customizable software, allowing customers to extend a data model with new data attributes. See how to design flexible systems, while using efficient SQL queries.
  • Hierarchies: Tree-structured data relationships are common, but working with trees in SQL usually implies recursive queries. There are a few solutions to solve this more cleanly.
  • ActiveRecord Dos and Dont’s: Web development frameworks have popularized the use of design patterns, but when it comes to multi-table queries, complex views, and assignment of OO responsibilities, ActiveRecord falls short as a one-size-fits-all Domain Model.
Photo of Bill Karwin

Bill Karwin

Karwin Software Solutions

Bill Karwin has been a software developer and technical writer since 1988. He is widely known for his talent for explaining complex topics and practical techniques with accuracy and a little humor. Recently he worked as the Product Engineering Manager developing the award-winning Zend Framework library for PHP 5.

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Picture of Bryan Basham
Bryan Basham
07/22/2009 5:43pm PDT

Excellent! Another high quality presentation. Great content on DB pattern. Very well organized. Great use of examples and diagrams.

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