Chapter 3. Using Collections
Conceptually, "array" has been a colloquial term in programming glossaries. It refers to a list of similar elements. In Oracle, an array is known by the name, collection. A collection consists of a list of elements of the same type, where each element can be identified by its index or subscript.
A collection works on the same philosophy as an array, a queue, or a linked list works. Collections provide wide scope of usability and applications in database programming. Besides being a performance booster, collections can also be used for data caching mechanisms in programs. It can also be used as database columns, type attributes or subprogram parameters. In this chapter, we shall perform a detailed study on collections, its types and usage in the following topics:
Collections—an overview
Categorization
Selection of an appropriate collection type
Associative arrays
Nested tables
Varray
Collections—a comparative study
PL/SQL collection methods
Manipulating collection elements...
