Oracle® PL/SQL® Interactive Workbook, Second Edition By Benjamin Rosenzweig, Elena Silvestrova
Table of Contents
In this Chapter, you will learn about:
Through out this book you have explored different types of PL/SQL identifiers or variables that represent individual elements (for example, a variable that represents a grade of a particular student). However, often in your programs you want to have the ability to represent a group of elements (for example, the grades for a class of students). In order to support this technique, PL/SQL provides collection datatypes that work just like arrays available in other third-generation programming languages.
A collection is a group of elements of the same datatype. Each element is identified by a unique subscript that represents its position in the collection. In this chapter you will learn about two collection datatypes: table and varray. In addition, you will learn about multilevel collections that have been introduced in Oracle 9i and are not supported by the previous releases.