"the basic building block of an application,contain user interface elements, such as tabs, lists, buttons, items, and regions."
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1.2
Page
Page Rendering
"lists user interface controls and logic that are executed when a page is rendered. Page Rendering is the process of generating a page from the database
Show Page is the page rendering process. It assembles all the page attributes (including regions, items, and buttons) into a viewable HTML page."
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1.3
Page
Page Processing
"Lists logic controls (such as computations and processes) that are evaluated and executed when the page is processed.
Accept Page performs page processing. It performs any computations, validations, processes, and branching.
When you request a page using a URL, the engine is running Show Page. When you submit a page, the Application Express engine is running Accept Page or performing page processing during which it saves the submitted values in the session cache and then performs any computations, validations, or processes."
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1.4
Condition
Condition
A small unit of logic that helps you control the display of regions, items, buttons, and tabs as well as the execution of processes, computations, and validations.
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1.4.1
Condition Type
Current page in Expression 1
"3,100,203
If the current page is 100, then this condition evaluates to true and the condition passes."
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1.4.2
Condition Type
Exists (SQL query returns at least one row)
"SELECT 1 FROM employees WHERE department_id = :P101_DEPTNO"
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1.4.3
Condition Type
PL/SQL Expression
NVL(:MY_ITEM,'NO') = 'YES'
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1.5
Session State Management
Session
A session is a logical construct that establishes persistence (or stateful behavior) across page views
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1.5.1
Session State Management
Referencing Session State
"1. SQL --> :MY_ITEM --> Standard bind variable syntax for items whose names are no longer than 30 characters. Use this syntax for references within a SQL query and within PL/SQL.
2. PL/SQL --> V('MY_ITEM') --> PL/SQL syntax referencing the item value using the V function.
3. PL/SQL --> NV('MY_NUMERIC_ITEM') --> Standard PL/SQL syntax referencing the numeric item value using the NV function.
4. Static text (exact) --> &MY_ITEM. --> Static text. Exact substitution."
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1.5.2
Session State Management
Setting Session State
When a user submits a page, the Application Express engine automatically stores values typed into fields (items) in session state.
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1.5.3
Session State Management
Clearing Session State
"Uses standard f?p syntax to clear the cache
1. Clearing Cache by Item
2. Clearing Cache by Page
3. Clearing Cache for an Entire Application
4. Clearing Cache for the Current User Session"
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1.6
Understanding URL Syntax
Understanding URL Syntax
"The URL that displays for each page identifies the location of Oracle Application Express, the address of Oracle Application Express, the application ID, the page number, and the session ID.
Using f?p Syntax:
f?p=App:Page:Session:Request:Debug:ClearCache:itemNames:itemValues:PrinterFriendly
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1.7
Substitution Strings
Substitution Strings
"You can use substitution strings within a page template or region source to replace a character string with another value. As you design your application and enable users to edit items, you use substitution strings to pass information.
You can use substitution strings in Application Builder in the following ways:
* Include a substitution string within a template to reference component values
* Reference page or application items using &ITEM. syntax
* Use built-in substitution strings to achieve a specific type of functionality
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