Draw one query tree for the given the following relationalalgebra query
?pname,phone(PATIENTS?DOCTOR?APPOINTMENTS)- ?R1.pname,R1.phone (?R1.pid=R2.pid (?R1.did=?R2.did(?R1(PATIENTS?DOCTOR?APPOINTMENTS) x?R2(PATIENTS?DOCTOR?APPOINTMENTS))))
?pname,phone(PATI ENTSP, DOCTORD APPOINTMENTS)-nR1.pname,R1.phone (oR1.pid-R2.pid (oR1.did- R2.did (pR1(PATIENTSDaDOCTORDaAPPOINTMENTS) x ?R2(PATIENTSP. DOCTOR> APPOINTMENTS)))) Show transcribed image text
Expert Answer
An answer will be send to you shortly. . . . .