PostgreSQL vs. MySQL
Building better databases
By Brian Jepson
To many people, PostgreSQL and MySQL seem like similar, alternative databases. Both are quickly gaining popularity. Based on the track records of older versions, there's a lot of debate over the speed of PostgreSQL and the durability of MySQL. But times have changed and each database has progressed. On both counts, the two packages are the closest they've ever been, so when deciding which to use in a Web application, a developer doesn't always have a clear winner.
MySQL's claim to fame is that it provides a reasonable set of features, such as built-in SQL functions, that follow the 80/20 rule: It has the 20 percent of SQL capabilities that are needed for 80 percent of database applications. Developers of simple applications can live without the remaining features, such as stored procedures and subqueries, or can work around them with creative client-side programming.
PostgreSQL, on the other hand, provides more features than MySQL. These include more SQL functions, server-side procedural languages, and sophisticated methods for date manipulation. PostgreSQL also offers object-relational capabilities and geometric data types. If you're developing an application that has highly complex business rules, PostgreSQL lets you handle business logic on the database server.
The ACID Test
A good way to differentiate databases and test overall quality is to perform an ACID test. ACID is an acronym that describes four properties of a robust database system: atomicity, consistency, isolation, and durability.
