MACROMEDIA COLDFUSION MX 61-DEVELOPING COLDFUSION MX, Develop Manual

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620 Chapter 28: Charting and Graphing Data
In this example, the data from the query column AvgByDept supplies the data for the y-axis, and
the query column Dept_Name provides the data for the x-axis.
The resulting chart looks like the following:
Administering charts
Use the ColdFusion MX Administrator to administer charts. In the Administrator, you can
choose to save cached charts in memory or to disk. You can also specify the number of charts to
cache, the number of charting threads, and the disk file for caching images to disk.
ColdFusion caches charts as they are created. In that way, repeated requests of the same chart load
the chart from the cache rather than having ColdFusion render the chart over and over again.
Note: You do not have to perform any special coding to reference a cached chart. Whenever you use
the
cfchart
tag, ColdFusion inspects the cache to see if the chart has already been rendered. If so,
ColdFusion loads the chart from the cache.
The following table describes the settings for the ColdFusion charting and graphing engine:
Option Description
Cache Type Set the cache type. Charts can be cached in memory or to disk. Caching in
memory is faster, but more memory intensive.
Maximum number of
images in cache Specify the maximum number of charts to store in the cache. When the limit
is reached, the oldest chart in the cache is deleted to make room for a new
one.
The maximum number of charts you can store in the cache is 250.
Max number of
charting threads Specify the maximum number of chart requests that can be processed
concurrently. The minimum number is 1 and the maximum is 5. Higher
numbers are more memory intensive.
Disk cache location When caching to disk, specify the directory in which to store the generated
charts.