Databases Reference
In-Depth Information
Figure 6-1.
Simplified APEX request/response
Phase one (ACCEPT) of servicing the user's requests is to process the current page and the user's
input. Because the state of the connection from the pool cannot be guaranteed to match the
requirements of the user's APEX session, the first thing that APEX does is to alter the session, setting the
desired NLS parameters and session settings. Figure 6-2 shows this portion of phase one processing.
Once the database session is in the proper state, APEX then begins checking to see if the APEX
session is still valid, whether the user has authorization to run the page, retrieving session state from the
APEX data dictionary tables, setting session state that may have been altered by the user, and then
running the page processing components as defined in the metadata.
The last steps of the processing is to decide which programmatic branch to take, which in turn
decides which page will then be rendered and sent to the user. APEX always takes the first branch whose
condition evaluates to true.
Figure 6-2.
APEX page phases
