November 2008
Intermediate to advanced
592 pages
20h 13m
English
Content preview from Introduction to Database Systems
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CHAPTER 4
RELATIONAL ALGEBRA AND CALCULUS
After reading this chapter, the reader will understand:
- Different query languages used to extract data from the database
- Difference between relational algebra and relational calculus
- Various unary relational algebra operations like select, project, and rename
- Various binary relational algebra operations like set operations, joins, and division operation
- Various set operations like union, intersection, difference, and cartesian product operation
- Different types of joins like equijoin, natural, and outer joins (left, right, and full outer join)
- The aggregate functions that are used to perform queries, which are mathematical in nature
- Two forms of relational calculus, namely, tuple relational calculus ...
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