Computer Sciences > GATE 2014 SET-3 > Relational Algebra
What is the optimized version of the relation algebra expression πA₁ (πA₂ (σF₁ (σF₂ (r)))), where A₁, A₂ are sets of attributes in r with A₁ ⊆ A₂ and F₁, F₂ are Boolean expressions based on the attributes in r?
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