Download Oracle Database Application Express User's Guide

Understanding Regions
See Also:
"Customizing Templates" on page 7-22
Utilizing Region Caching
Enabling region caching is an effective way improve the performance of static regions
such as regions containing lists that do not use conditions or regions containing static
HTML.
When you enable region caching, the Application Express engine renders a region
from a cached (or stored) respository instead of rendering it dynamically. Keep in
mind that the actual session identifiers are not cached. Instead, the Application
Express engine caches a &SESSION. substitution string and the current session
rendering the cached region is substituted on display. For example, if a region contains
a link and the link includes a session, the exact session is not cached to ensure that the
links works for all sessions.
The Application Express engine only renders a region from cache if it meets the
defined condition. Additionally, regions can be cached specific to a user or cached
independent of a user.
See Also:
"Cache" on page 4-45
Enabling Region Caching To enable region caching:
1.
Navigate to the appropriate Page Definition. See "Accessing a Page Definition" on
page 4-19.
2.
Under Regions, click the region name.
The Region Definition appears.
3.
4.
Scroll down to Cache and specify the following:
a.
Caching - Select Cached to cache the region independent of the user. Select
Cached by User to cache the region specific to a given user.
b.
Timeout Cache After - Identify how long the cached region remains valid.
c.
Cache Condition Type - Select a condition type from the list. If the condition
returns false, the region is rendered dynamically and is not be cached. If the
condition returns true, the region is cached.
d.
Expression 1 and Expression 2 - Enter values based on the specific condition
type selected.
Click Apply Changes.
Specifying a Static Region ID
Specifying a static region ID is useful when creating custom JavaScript or cascading
stylesheets. You can use the Static ID attribute on the Edit Region page to uniquely
identify a region. You can then reference the region using the #REGION_STATIC_ID#
substitution string in a region templates, the header, the footer, or the body.
To specify a static region ID:
1.
Navigate to the appropriate Page Definition. See "Accessing a Page Definition" on
page 4-19.
The Region Definition appears.
2.
Under Identification, enter a value in Static ID.
3.
Click Apply Changes.
Controlling Page Layout and User Interface 7-7