I think the short answer is no, but the game is changing rapidly, and Amazon is at the vanguard.
SimpleDB basically acts like a big structured bucket.
The Model is represented by Domains. A Domain can have Attributes. Attributes are key/value pairs.
There is no schema attached to Domains, you can PUT any combination of attribute-values in the domain:
PUT (item, 123), (description, sweater), (color, blue), (color, red)
PUT (item, 456), (description, dress shirt), (color, white), (color, blue)
PUT (item, 789), (description, shoes), (color, black), (material, leather)
The real issue here is that developers are strongly tied to the RDBMS. Frameworks assume you are running on top of a relational database, so there is an instant barrier to entry. However, I suspect it won’t be long before the first set of libraries and drivers for SimpleDB are developed.
The much bigger issues are in the features that SimpleDB doesn’t have:
- No ACID
- No transactions (see ACID, above)
- No relationships
- No data integrity
- No SQL
SQL is actually pretty incredible – it makes accessing structured data very simple. If you’ve ever played with other types of data store you miss SQL almost instantly (Prevayler, anyone?).
All of that said, Amazon continues to lead the way with Web Services. Consider SimpleDB a warning shot to the database incumbents.