0 votes 0 votes Let R1(a,b) = {(2,3),(3,2),(2,4),(2,5)},R2={(2,2),(3,3)} then find $\Pi_{AB(R1)}/\Pi_{B}(\sigma _{c>3}(R2))$ Databases databases relational-algebra + – Anjan asked Nov 9, 2017 Anjan 730 views answer comment Share Follow See all 6 Comments See all 6 6 Comments reply Show 3 previous comments joshi_nitish commented Nov 10, 2017 reply Follow Share it should be, πAB(R1) / empty = πA(R1) // for above qsn 1 votes 1 votes Sukannya commented Nov 10, 2017 reply Follow Share What are R2's attributes? 0 votes 0 votes pradeepchaudhary commented Mar 24, 2018 reply Follow Share why only (A) attribute of R1 is printed? 0 votes 0 votes Please log in or register to add a comment.