On Thu, Nov 29, 2012 at 9:42 PM, Alexrk 
An interesting idea. But the purpose of a database is (in contrast to Commons) to create "produced works" from it. This would be almost impossible, if each data item or data set has a different licence.

I was thinking that licenses would apply to a dataset, not to individual items. I don't believe database rights apply to individual items, only to entire datasets (or substantial portions of them), so it would make sense that data licenses would apply at the same level. 

I'd imagine that we don't want to store databases composed of items that require individual licenses (e.g. images or lengthy texts), at least to begin with.

The status of "produced works" would presumably depend on the provisions of the data license. Some might be placed under the same license, or require attribution (e.g. for the ODBL), or not require a license at all.

Deciding it's all too hard may be one option. But we should be clearly aware of the long-term consequences of not tracking licenses before we make that decision. I'm not convinced we have thought this through enough yet.