How to evaluate a tree of RA operators?

computer science


Query evaluation 

• How to evaluate a tree of RA operators? – Logical and physical optimization (there are many interactions!) – Query evaluation plan is the result 

• Logical optimization 

 Searching for logically equivalent query expressions 

 To determine the cost of a query we need to have physical QEP 

 Heuristics without the exact QEPs? (size of result ~ QEP?) 

• Physical optimization 

 Searching for optimal mathods for evaluationg RA operators 

 Physical optimization intervenes with the logical optimization 

 Evaluation of RA operator trees 

 Algorithms of RA operators (see previous lecture)

Related Questions in computer science category