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What are the quantifiers (marked as “?”) in the following tuple relational calculus query: List of project numbers that involve an employee whose last name is ‘Wong’,  as manager of the controlling department for the project. ans :=    { P.pNumber | projects(P) and    ((? M) (? D)      (employee(M) and department(D) and P.dNumber = D.dNumber and D.mgrSSN = M.eSSN and M.lName = ‘Wong’ ) ) };

What is the purpose of a relational algebra project operation?

Which constraint will guarantee that a column of a table will have only a set of permissible values?

What is the equivalent relational algebra operation sequence for the WinRDBI njoin operation?

The entity integrity constraint for a table is specified through __________________________.

If you anticipate running a particular SQL query often, you can improve overall performance by saving the query in a __________________.

How many no. of output rows will be created by the relational algebra product operation on table L (with m rows) and table R (with n rows)?

When a relational algebra project operation will not require sorting?

Which constraint will enforce entity integrity for a table?

Ryan Company maintains a defined benefit pension plan for its employees. For the fiscal year ended December 31 of the current year, it reported a pension liability. This liability is the amount by which the