Relational Algebra A database records information about athletes competing at the Olympics. An athlete competes for a particular country in one or more events. Events take place at a scheduled day and time in a particular venue. The result (rank) is recorded for all athletes in the final of the event. The medal (gold, silver or bronze) is also recorded for the medal winners in the event. Note that we are not considering team sports or heats in this example – only individuals competing in the finals. The schema for this database is as follows: (Note that primary keys are shown underlined, foreign keys in bold). ATHLETE ( AthleteNo , AthleteName, CountryName) COUNTRY ( CountryName , NumberOfCompetitors) EVENT (EventName, ScheduledStart, VenueName ) VENUE (VenueName, City, Capacity) FINAL ( AthleteNo , EventName , Rank, Medal) Provide relational algebra (NOT SQL) queries to find the following informaList the name and country of all athletes. List the event name and scheduled...
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