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Copyright © 2004 Pearson Education, Inc.
Copyright © 2004 Pearson Education, Inc.
Chapter 6
The Relational Algebra and Relational Calculus
Slide 6-3Elmasri and Navathe, Fundamentals of Database Systems, Fourth Edition
Copyright © 2004 Pearson Education, Inc.
FIGURE 6.1Results of SELECT and PROJECT operations. (a) (DNO=4 AND
SALARY>25000) OR (DNO=5 AND SLARY>30000)(EMPLOYEE). (b) SEX,
SALARY(EMPLOYEE).
Slide 6-4Elmasri and Navathe, Fundamentals of Database Systems, Fourth Edition
Copyright © 2004 Pearson Education, Inc.
FIGURE 6.2Results of a sequence of operations. (a) FNAME, LNAME, SALARY
(DNO=5(EMPLOYEE)). (b) Using intermediate relations and renaming of attributes.
Slide 6-5Elmasri and Navathe, Fundamentals of Database Systems, Fourth Edition
Copyright © 2004 Pearson Education, Inc.
FIGURE≈6.3Results of the UNION operation RESULT €RESULT1 RESULT2.
Slide 6-6Elmasri and Navathe, Fundamentals of Database Systems, Fourth Edition
Copyright © 2004 Pearson Education, Inc.
FIGURE≈6.4The set operations UNION, INTERSECTION, and MINUS. (a) Two union-compatible relations. (b) STUDENT INSTRUCTOR. (c) STUDENT INSTRUCTOR. (d) STUDENT – INSTRUCTOR. (e) INSTRUCTOR – STUDENT
Slide 6-7Elmasri and Navathe, Fundamentals of Database Systems, Fourth Edition
Copyright © 2004 Pearson Education, Inc.
FIGURE≈6.5aThe CARTESIAN PRODUCT (CROSS PRODUCT) operation.
Slide 6-8Elmasri and Navathe, Fundamentals of Database Systems, Fourth Edition
Copyright © 2004 Pearson Education, Inc.
FIGURE≈6.5bThe CARTESIAN PRODUCT (CROSS PRODUCT) operation.
Slide 6-9Elmasri and Navathe, Fundamentals of Database Systems, Fourth Edition
Copyright © 2004 Pearson Education, Inc.
FIGURE≈6.5cThe CARTESIAN PRODUCT (CROSS PRODUCT) operation.
Slide 6-10Elmasri and Navathe, Fundamentals of Database Systems, Fourth Edition
Copyright © 2004 Pearson Education, Inc.
FIGURE≈6.6Result of the JOIN operation DEPT_MGR DEPARTMENT JOIN MGRSSN=SSN EMPLOYEE .
Slide 6-11Elmasri and Navathe, Fundamentals of Database Systems, Fourth Edition
Copyright © 2004 Pearson Education, Inc.
FIGURE≈6.7Results of two NATURAL JOIN operations. (a) PROJ_DEPT PROJECT * DEPT. (b) DEPT_LOCS DEPARTMENT * DEPT_LOCATIONS.
Slide 6-12Elmasri and Navathe, Fundamentals of Database Systems, Fourth Edition
Copyright © 2004 Pearson Education, Inc.
FIGURE≈6.8The DIVISION operation. (a) Dividing SSN_PNOS by SMITH_PNOS. (b) T R ÷ S.
Slide 6-13Elmasri and Navathe, Fundamentals of Database Systems, Fourth Edition
Copyright © 2004 Pearson Education, Inc.
FIGURE≈6.9The AGGREGATE FUNCTION operation.
Slide 6-14Elmasri and Navathe, Fundamentals of Database Systems, Fourth Edition
Copyright © 2004 Pearson Education, Inc.
FIGURE≈6.10A two-level recursive query.
Slide 6-15Elmasri and Navathe, Fundamentals of Database Systems, Fourth Edition
Copyright © 2004 Pearson Education, Inc.
FIGURE≈6.11The result of a LEFT OUTER JOIN operation.
Slide 6-16Elmasri and Navathe, Fundamentals of Database Systems, Fourth Edition
Copyright © 2004 Pearson Education, Inc.
FIGURE≈6.12A relational database schema for a LIBRARY database.
Slide 6-17Elmasri and Navathe, Fundamentals of Database Systems, Fourth Edition
Copyright © 2004 Pearson Education, Inc.
FIGURE≈6.13A database state for the relations T1 and T2.
