PSNC have published a comparison of MySQL 4.1 and PostgreSQL 8.0.
If you’re interested to know what features you’re missing out on by using MySQL rather than PostgreSQL, the comparison table provides a handy summary. MySQL 5.0 (in development) is getting closer to PostgreSQL’s impressive feature set, with Views and Stored Procedures on the list. According to the article, however, MySQL still beats PostgreSQL in terms of performance. Details of a number of benchmarks are given.
MySQL has certainly made progress since I began using it, adding support for subqueries (in 4.1), full text searching with boolean, and transactions (InnoDB).
From the article:
MySQL is simplier than PostgreSQL but much faster. MySQL doesn’t support many advanced features that may be important in huge relational and complicated databases. But for JRA1 measurement architecture MySQL should be adequate (we probably wouldn’t use the most advanced features).
Currently, MySQL is a staple of the LAMP (Linux, Apache, MySQL, and PHP) architecture, pre-installed on many hosting accounts and bundled with many operating systems. This makes it very attractive to novices and intermediate web programmers, as it is relatively easy and cheap to get started playing around with it. With its expanding feature set and dual license, MySQL is looking to expand its usage in other market segments.
The article also contains link to more detailed comparison information, such as the feature comparison page at mysql.com.
Via Open Source Versus, check it out.