Currently looking to standardize on a database that will scale as our application grows. Anticipated DB size could have the potential to grow to several Terabytes (emails, images, .wav files, documents, etc), initially DB size will probably not exceed a few hundred Gigabytes. In order of importance of feature functionality: reliability (uptime), scalability, and speed.
Looking for objective opinion/resource comparing PostgreSQL to MS SQL, MYsql, and Interbase. Assuming all things equal, do not include OS as part of the comparison.