Computers and Technology, 02.06.2020 21:57 SiegeHatake4534

Consider the following relational schema, where the primary keys are Bold,
Students(sid, sname, address, dept_id)
Courses(cid, cname, dept_id)
Departments(dept_id, dname, college)
Grades(sid, cid, year, semester, grade)
Write the following queries in SQL. Only use the tables that are absolutely needed for the corresponding query.
1. Find the sids and snames of students who took "Database" course (i. e., cname = ‘Database’) in Fall 2019.
2. Find the average grade of all the students who took "CS327" (i. e., cid=‘CS327’) in Fall 2019. You can assume grade is a numerical attribute.
3. Find the number of distinct courses offered by each department in Fall 2019.
4. Find the sids of students who have taken at least 10 different courses offered by "Computer Science" department (i. e., dname = ‘Computer Science’).

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Consider the following relational schema, where the primary keys are Bold,
Students(sid, snam...

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