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Database Systems: The Complete Book- P4

Database Systems: The Complete Book- P4: Database Systems and Database Design and Application courses offered at the junior, senior and graduate levels in Computer Science departments. Written by well-known computer scientists, this introduction to database systems offers a comprehensive approach, focusing on database design, database use, and implementation of database applications and database management systems | 276 CHAPTER 6. THE DATABASE LANGUAGE SQL StarsIn movieTitle movieYear starName MovieStar name address gender birthdate MovieExec name address cert netWorth Studio name address presC describe the tuples that would appear in the following SQL expressions a Studio CROSS JOIN MovieExec b Starsln NATURAL FULL OUTER JOIN MovieStar c Starsln FULL OUTER JOIN MovieStar ON name starName Exercise 6.3.8 Using the database schema Product maker model type PC model speed ram hd rd price Laptop model speed ram hd screen price Printer model color type price write an SQL query that will produce information about all products PC s laptops and printers including their manufacturer if available and whatever information about that product is relevant i.e. found in the relation for that type of product . Exercise 6.3.9 Using the two relations Classes class type country numGuns bore displacement Ships name class launched from our database schema of Exercise 5.2.4 write an SQL query that will produce all available information about ships including that information available in the Classes relation. You need not produce information about classes if there are no ships of that class mentioned in Ships. Exercise 6.3.10 Repeat Exercise 6.3.9 but also include in the result for any class C that is not mentioned in Ships information about the ship that has the same name C as its class. Exercise 6.3.11 The join operators other than outerjoin we learned in thi. section are redundant in the sense that they can always be replaced by select-from-where expressions. Explain how to write expressions of the following forms using selcct-from-where a R CROSS JOIN S b R NATURAL JOIN S c R JOIN S ON C where C is an SQL condition. 1 6.4. FULL-RELATION OPERATIONS 277 6.4 Full-Relation Operations In this section we shall study some operations that act on relations as a whole rather than on tuples individually or in small numbers as do joins of several relations for instance . First we deal with the fact that SQL