DMBS Optimization It is interesting to observe that the typical DBMS will then optimize" the query by transforming the algebraic expression to one that can be executed faster. Key optimizations: 1.Push selections down the tree. 2.Eliminate unnecessary projections. 88 DMBS Optimization z It is interesting to observe that the typical DBMS will then “optimize ” the query by transforming the algebraic expression to one that can be executed faster. z Key optimizations: 1. Push selections down the tree. 2. Eliminate unnecessary projections