User Guide

116 Chapter 8 Handling Complex Data with Structures
About Arrays
Traditionally, an array is a tabular structure used to hold data, much like a
spreadsheet table with clearly defined limits and dimensions. A two-dimensional
(2D) array is like a simple table. In ColdFusion, you typically use arrays to
temporarily store data. For example, if your site allows users to order goods online,
you can store their shopping cart contents in an array. This allows you to make
changes easily without committing the information, which the user can change
before completing the transaction, to a database.
Conventional fixed-size 2D array
A 2D array is like a cube made up of individual cells, as the following figure shows:
ColdFusion arrays differ somewhat from traditional arrays because they are
dynamic. For example, in a conventional array, array size is constant and
symmetrical, whereas in a ColdFusion 2D array you can have rows of differing
lengths based on the data that has been added or removed. The following figure
represents a ColdFusion 2D array: