we have not explained the database schema on purpose, because we are strongly discouraging our users to work directly with database and instead we encourage the usage of Sitefinity API.
Here are the documents explaining Blogs and Events API respectively:
The reason we are discouraging users to work directly with database lays simply in backward compatibility. Namely, as you may know we will be introducing the new ORM tool in Sitefinity in v 4.0 - which will introduce surely some changes in the database schema. While we will maintain full backward compatibility for the API all our users who coded directly against database will have to rewrite their code.
I hope you'll find this information helpful. Let us know if there is anything else we can do for you.
All the best,
the Telerik team
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