2.2 Optimize the following two relational algebra queries (Your marks will depend on how well you...
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2.2 Optimize the following two relational algebra queries (Your marks will depend on how well you present the key ideas of query optimization in your answer). In addition to this, draw the query trees correspond to queries before and after your optimisation. (a) TCUSTOMER.name, EMPLOYEE.name,date (0(CID=CustomerI D) A(EID=Employeel D) A(price>150) (BOOKING EMPLOYEE x CUSTOMER)) (2 Mark) (Б) твнс1.CID, BHC2.CID,BнС1.Date (0 (внс1.CID<BHC2.CID) Л(ВHC1.nате-ВНС2.патe) Л(ВНС1.Date-ВНС2.Date) (рвнс1 ((ВООKING HOTEL) HOTEL) 'CID=CustomerID CUSTOMER))) CUSTOMER) x PBHC2((BOOKING (2 Mark) DACID=CustomerID 2.2 Optimize the following two relational algebra queries (Your marks will depend on how well you present the key ideas of query optimization in your answer). In addition to this, draw the query trees correspond to queries before and after your optimisation. (a) TCUSTOMER.name, EMPLOYEE.name,date (0(CID=CustomerI D) A(EID=Employeel D) A(price>150) (BOOKING EMPLOYEE x CUSTOMER)) (2 Mark) (Б) твнс1.CID, BHC2.CID,BнС1.Date (0 (внс1.CID<BHC2.CID) Л(ВHC1.nате-ВНС2.патe) Л(ВНС1.Date-ВНС2.Date) (рвнс1 ((ВООKING HOTEL) HOTEL) 'CID=CustomerID CUSTOMER))) CUSTOMER) x PBHC2((BOOKING (2 Mark) DACID=CustomerID
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Related Book For
Fundamentals of Database Systems
ISBN: 978-0136086208
6th edition
Authors: Ramez Elmasri, Shamkant Navathe
Posted Date:
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