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Project Operation Notation: Π有44) where A1,A2 are attribute names and ris a relation name. The result is defined as the relation of k columns obtained by erasing the columns that are not listed Duplicate rows removed from result,since relations are sets Example:To eliminate the dept name attribute of instructor IIID,name,salary(instructor) Database System Concepts-6th Edition 6.5 @Silberschatz,Korth and SudarshanDatabase System Concepts - 6 6.5 ©Silberschatz, Korth and Sudarshan th Edition Project Operation Notation: where A1 , A2 are attribute names and r is a relation name. The result is defined as the relation of k columns obtained by erasing the columns that are not listed Duplicate rows removed from result, since relations are sets Example: To eliminate the dept_name attribute of instructor ID, name, salary (instructor) ( ) , , 2 , 1 r k  A A  A
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