Questions from Database Systems

Q: Explain the concept of physical data independence and its importance in database

Explain the concept of physical data independence and its importance in database systems.

Q: With dept. total (dept. name, value) as

With dept. total (dept. name, value) as (select dept. name, sum (salary) from instructor Group by dept. name), dept. total avgas (value) as (Select avgas (value) from dept. total) Select dept. name Fr...

Q: Using the university schema, write an SQL query to find the

Using the university schema, write an SQL query to find the name and ID of those Accounting students advised by an instructor in the Physics department.

Q: Consider the Oracle Virtual Private Database (VPD) feature described in

Consider the Oracle Virtual Private Database (VPD) feature described in Sec- ton 9.8.5 and an application based on our university schema. a. What predicate (using a sub query) should be generated to a...

Q: Using the university schema, write an SQL query to find the

Using the university schema, write an SQL query to find the names of those departments whose budget is higher than that of Philosophy. List them in al- phonetic order.

Q: Using the university schema, use SQL to do the following:

Using the university schema, use SQL to do the following: For each student who has retaken a course at least twice (i.e., the student has taken the course at least three times), show the course ID and...

Q: Using the university schema, write an SQL query to find the

Using the university schema, write an SQL query to find the IDs of those students who have retaken at least three distinct courses at least once (i.e., the student has taken the course at least two tim...

Q: Using the university schema, write an SQL query to find the

Using the university schema, write an SQL query to find the names and IDs of those instructors who teach every course taught in his or her department (i.e., every course that appears in the course rela...

Q: Using the university schema, write an SQL query to find the

Using the university schema, write an SQL query to find the name and ID of each History student whose name begins with the letter ‘D’ and who has not taken at least five Music courses.

Q: Write the SQL statements using the university schema to perform the following

Write the SQL statements using the university schema to perform the following operations: a. Create a new course “CS-001”, titled “Weekly Seminar”, with 0 credits. b. Create a section of this course i...