Rest of the Talk
unnesting comprehensions,
unnesting nested queries,
Notes:
The rest of my talk is organized as follows: My OODB calculus is based on the theory of monoids from abstract algebra. It supports only one traversal mechanism called monoid comprehensions. To support the claim that this calculus is effective, I present a compositional query unnesting algorithm that unnests many forms of nested queries, which improves evaluation performance. To translate the calculus into execution plans and to unnest all other forms of nested queries, I will present an intermediate algebra similar to the nested relational algebra. Then I describe a prototype OQL optimizer based on this theory. Finally, I list some of the research questions that I am currently addressing or planning to address in the future.