In a typical enterprise scenario with in-house development, you might have dev, staging, and production environments. You might use SVN to contain ongoing development work in a trunk, with patches being stored in branches, and your released code going into appropriately named tags. Migrating binaries from one environment to the next may be as simple as copying them to middle-ware servers, GAC'ing things that need to be GAC'ed, etc. In coordination with new revisions of binaries, databases are updated, usually by adding stored procedures, views, and adding/adjusting table schema.
In a Sharepoint environment, you might use a similar version control scheme. Custom code (assemblies) ends up in features that get installed either manually or via various setup programs. However, some of what needs to be promoted from dev to staging, and then onto production might be database content that supports the custom code bits.
If you've managed an enterprise Sharepoint environment, please share thoughts on how you manage promotion of code and content changes between environments, while protecting your work and your users, and keeping your sanity.
Best Answer
I assume when you talk about database content you are referring to the actual contents contained in a site a or a list.
Probably the best way to do this is to use the stsadm import and export commands to export and import content from one environment to another. (Don't use backup/restore when going from one environment to another.)