Continue working on the same project

• Doing the optimizations!
• Comprehensive testing and properties.
• Extending the syntax of variational relational algebra to include naming and aggressive functions.
• Introducing a new value in SQL for invalid values instead of using NULL.
• Writing the optimization rules and incorporating the type environment (vschema/table schema) with them.
• Proving that the optimization rules are type preserving instead of proving that they're semantic preserving. This is more relaxed property to prove.

Side projects

• Generating a large scale real-world VDB
  • Using evaluation history, eg., branching from the wikipedia db
  • Using tools that are based on wikipedia. Look into software mediawiki
• Formalizing VDBMS properties and proving them