1. Introduction to Oracle Application Express

2. What is Application Express?
Formerly called HTML-DB, Project Marvel, Einstein
It was a really bad name for a very useful product
A tool for developing and deploying database-centric, web-based applications
works with Internet Explorer, Netscape, FireFox, Opera, etc.
bundled with Oracle 10G+ (works with Oracle )
provides a wizard driven development environment
requires minimal knowledge of database & web development
has many pre-configured application templates
Reports, charts, data entry forms
Drill down, hypertext linking, export to spreadsheet
uses customizable style sheets for uniform UI look & feel
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3. Architecture: Data Driven
Applications are data driven
All application pages are rendered in real time from metadata stored in the database
When you create or extend your application, no code is generated; instead metadata stored in the database is created or modified
The page-rendering engine reads the metadata, generates the HTML for the page, and send it to the browser.
Browser
Oracle Database
Oracle HTTP
Server
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4. Application Security Apps use authentication and authorization schemes
authentication: establishes the user’s identity before allowing access to the application
Username/password, secure key, digital certificates
Several preconfigured authentication schemes are available (single-sign on, LDAP, DAD credentials, ApEx accounts)
authorization: controls access to an application, a page or specific page components (region, item, button, etc.)
authorization either succeeds or fails
component authorization failures do not generate error messages
Application Express’ built-in security prevents
intentional attempts by a user to access session state belonging to someone else
inadvertent access to stale session state (belonging to the same user from an earlier time/session; mainly due to book-marking a page)
linking to an ApEx page out of context (for example, from a hyperlink in an - “deep linking”)
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5. The Application Express URL
The application URL identifies the location of the Oracle Application Express engine, the unique application ID, the page number, and the session ID.
Applications and app pages may have alphanumeric aliases.
Application aliases are unique within a workspace and page aliases are unique within each application.
When you run an application, the Application Express engine generates a session ID that serves as a key to your session.
Example:
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6. Developing in Application Express
Start up browser and enter URL
You’ll need a developer account which includes a workspace
Workspace: an area with the Application Express environment where applications are created
Are associated with one or more schemas
Can have one or more developers
Can hold one or more applications
Has an administrative account
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7. Application Express Components
Application Express’ development environment has three main components
Application Builder: used to build database-centric interactive Web applications
SQL Workshop: used to run SQL statements and SQL scripts, browse the database
Utilities: used to administer the application environment, export/import data, view system metrics/logs
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8. Application Builder
Used to build an HTML interface (or application) on top of database objects such as tables and procedures
Application: a collection of database-driven web pages linked together using tabs, buttons, or hypertext links.
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9. SQL Workshop
Used to view and manage database objects from a web browser
Execute SQL commands
Create or modify database objects
Up/Download and run SQL scripts
“Query by example” Interface
Browse the data dictionary
Used to import data into and export data from the database
Supported file formats include text (comma or tab delimited), XML documents and spreadsheets (import only)
Users can create and load a table directly from a spreadsheet without any SQL knowledge
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10. Utilities Used to administer the application environment
Data loading/Unloading
Generate DDL
Monitor application activity
Monitor database performance
Perform schema comparisons
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11. Application Builder Concepts
Application Builder is used to assemble an HTML interface (or application) on top of database objects such as tables and procedures.
Each application is a collection of pages linked together using tabs, buttons, or hypertext links.
A page is the basic building block of an application. Each page contains user interface elements, such as tabs, lists, buttons, items within containers called regions.
There are many different types of regions including report, form, chart, tree, HTML, etc.
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12. Generic Application Creation Workflow
Create Application
Create/Add Page
Create/Add Region
Create/Add Items
Create Branches
Create Processes
Create Validations
Create Computations
Create Page/Region/Item/Branch/Process/Validation/Computation
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13. Create Application Workflow
Select Create Application from Application Builder
Select ‘Create Application’
Give application a name
Add at least one page
Choose a ‘look and feel’ (theme)
Click CREATE button on Confirm screen
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14. Items (some call processes)
Pages
A page is the basic building block of an application.
Each page can have buttons and fields (called items), which are grouped into containers called regions.
Pages can also have application logic (or processes).
You can branch from one page to the next using conditional navigation; perform calculations (called computations); perform validations (such as edit checks); and display reports, calendars, and charts.
You view, create, and edit the controls that define a page by accessing the Page Definition page
Regions
Items (some call processes)
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15. Create/Add Page(s) Workflow
Open application for editing
Click Create Page button
Select page/region type
Name the page
Set page tab attributes
Enter page-type specific information/attributes
Confirm page creation
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16. Regions Pages consist of regions
Regions are containers which hold application components (reports, buttons, charts, etc.)
There are many different types of regions
Region attributes vary by region type
Regions can be created during the app creation process or added later as needed
Regions can be added by editing an existing page
The display of a region and/or its components can be conditional
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17. Create/Add Region(s) Workflow
Open application
Open page to be edited
Click on Create Icon in Regions Section
Create Icon
Select region type
Enter region-type specific information/attributes
Specify condition(s) for display
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18. Application Items/Components
Items are HTML components that appear in a region on a page.
There are two types of items:
Page items are placed on a page and have associated user interface properties, such as Display As, Label and Label Template.
Examples include a check box, date picker, display as text, file browse field, popup list of values, select list, or a text area.
Page items are associated with a region on the page
Application items are not associated with a page and therefore have no user interface properties.
You can use application items as global variable.
Items are created/edited in the Items section of the Page Definition page
Tip: prefix page item names with”Pnn-” where nn is the page number (example: P12_NAME)
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19. Create/Add Item(s) Workflow
Open application
Open page to be edited
Click on Create Icon in Items Section
Create Item
Select item type
Enter item-type specific information/attributes
Specify condition(s) for display
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20. Application Express Information
Tutorials, viewlets, forum, documentation, downloads
Pro Oracle Application Express
By Scott John, Spendolini Scott, Scott J.
Available in Sept, 2008
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21. Build Demo Application
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22. Introduction To Application Express
Application Builder Concepts

23. Application Builder Concepts
Application Builder is used to assemble an HTML interface (or application) on top of database objects such as tables and procedures. Each application is a collection of pages linked together using tabs, buttons, or hypertext links.
A page is the basic building block of an application. When you build an application in Application Builder, you create pages that contain user interface elements, such as tabs, lists, buttons, items, and regions.
There are many different types of pages/regions including report, form, chart, tree, HTML, etc.
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24. Application Builder Concepts
When you create an application in Application Builder, you link pages together using tabs, buttons, or hypertext links.
Each page can have buttons and items and can include application logic.
You can branch from one page to the next using conditional navigation, perform calculations and validations, and display reports, calendars, and charts.
You can generate reports, charts, and forms using built-in wizards, static HTML, or deliver more custom rendering with PL/SQL programming.
Hyperlink Button Tab
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25. Rendering and Processing Pages
The Application Express engine dynamically renders and processes pages based on data stored in Oracle database tables.
To view a rendered version of your application, you request it from the Application Express engine.
When you run an application, the Application Express engine relies on two processes:
Show Page is the page rendering process. It assembles all the page attributes (including regions, items, and buttons) into a viewable HTML page.
Accept Page performs page processing. It performs any computations, validations, processes, and branching.
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26. Items (some call processes)
Page Definition
A Page Definition is the basic building block of a page.
Each page can have buttons and fields (called items), which are grouped into containers called regions.
Pages can also have application logic (or processes).
You can branch from one page to the next using conditional navigation; perform calculations (called computations); perform validations (such as edit checks); and display reports, calendars, and charts.
You view, create, and edit the controls that define a page by accessing the Page Definition in the Page Definition page
Regions
Items (some call processes)
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27. Page Definition Page
The Page Definition page is divided into three sections:
Page Rendering: the process of generating a page from the database. The Page Rendering section lists user interface controls and logic that execute when a page is rendered.
Page Processing: occurs once a page is submitted. Typically a page is submitted when a user clicks a button. The Page Processing section lists logic controls (such as computations and processes) that are evaluated and executed when the page is processed.
Shared Components: lists common components that can be used by one or more pages within an application.
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28. Generic Application Creation Workflow
Create Application
Create/Add Page
Create/Add Region
Create/Add Items
Create Branches
Create Processes
Create Validations
Create Computations
Create Page/Region/Item/Branch/Process/Validation/Computation
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29. Application Creation Options
Create Application
From Scratch: Specify tabs, select a user interface theme, and many other options.
Based on an Existing Application: Create a copy of another application using the same user interface theme, but minus the pages.
Based on an Existing Table: Create an application based on existing tables. Includes a report page for each table, a form page to insert and update data, and a page containing a graphical chart.
Based on Spreadsheet:
Create an easily deployable application from a spreadsheet (or text file).
Build demo application
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30. Create Application Workflow
Select Create Application from Application Builder
Select ‘Create Application’
Give application a name
Add at least one page
Choose a ‘look and feel’ (theme)
Click CREATE button on Confirm screen
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31. Themes and Templates Templates: Themes:
HTML and CSS code that defines the layout and format of application components (reports, charts, buttons, links, tabs, menus, etc.)
control the look and feel of the components in your application.
templates are organized first by type (breadcrumb, button, calendar, label, list, page, popup list of values, region, and report) and then by template classes, identifying the purpose of the each template within that type.
Themes:
collections of templates that can be used to define the layout and style of an entire application.
the idea behind a theme is to provide a complete set of templates that accommodate every UI pattern that may be needed in an application.
Knowledgeable developers can define/customize their own themes and templates. This process requires knowledge of HTML, Cascading Style Sheets, and web design.
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32. Creating a Page
A page is the basic building block of an application. When you build an application in Application Builder, you create pages that contain user interface elements, such as tabs, lists, buttons, items, and regions.
You add a new page or add a component to an existing page by running the Create Page Wizard. You can access this wizard by:
Clicking Create Page on the Application home page.
Clicking Create on the Page Definition.
Click the Create link on the Developer toolbar and then select New Page.
Create Icon
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33. Create Initial Page (with app) Workflow
Applications are made up of pages
Pages can be created during app creation or added later
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34. Adding Page(s) Workflow
Open application for editing
Click Create Page button
Select page/region type
Name the page
Set page tab attributes
Enter page-type specific information/attributes
Confirm page creation
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35. Page/Region Types Wizard-driven Page Creation 11/9/2018
Blank Page(s): Creates one or more blank pages.
Report: Creates a report based on a custom SQL SELECT statement or a PL/SQL function returning a SQL SELECT statement
Chart: create three types of graphical charts: HTML, Scalable Vector Graphics (SVG), and Flash
Form: Creates a form interface with which users can update a single row or multiple rows within a table
Wizard: Create a wizard.
Calendar: Generates a calendar with monthly, weekly, and daily views.
Tree: Creates a a tree to graphically communicate hierarchical or multiple level data.
Login Page: Creates a login page
Access Control: Creates a page containing a access control list, enabling developers to control access to an application, individual pages, or page components
Page Zero: A page zero that functions as a master page. The Application Express engine renders all components you add to page zero on every page within your application.
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36. Regions Pages consist of regions
Regions are containers which hold application components (reports, buttons, charts, etc.)
There are many different types of regions
Region attributes vary by region type
Regions can be created during the app creation process or added later as needed
Regions can be added by editing an existing page
The display of a region and/or its components can be conditional
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37. Adding Region(s) Workflow
Open application
Open page to be edited
Click on Create Icon in Regions Section
Create Icon
Select region type
Enter region-type specific information/attributes
Specify condition(s) for display
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38. Application Items/Components
There are two types of items: page items and application items.
Page items are placed on a page and have associated user interface properties, such as Display As, Label and Label Template.
Examples of page-level items include a check box, date picker, display as text, file browse field, popup list of values, select list, or a text area.
Page items are associated with a region on the page
Application items are not associated with a page and therefore have no user interface properties.
You can use an application item as a global variable.
Tip: prefix page item names with”Pnn-” where nn is the page number (example: P12_NAME)
Items are created/edited in the Items section of the Page Definition page
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39. Adding Item(s) Workflow
Open application
Open page to be edited
Click on Create Icon in Items Section
Create Item
Select item type
Enter item-type specific information/attributes
Specify condition(s) for display
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40. Branches
A branch is an instruction to go to a specific page, procedure, or URL. For example, you can branch from page 1 to page 2 after page 1 is submitted.
You create a new branch by running the Create Page Branch Wizard and specifying Branch Point and Branch Type. The Branch Type defines the type of branch you are creating.
The page number of the page to which you want to branch
PL/SQL procedure which ultimately renders a branch target page
A URL address
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41. Branch Points
You can control when a branch executes by making a selection from the Branch Point list.
Branch Point Options:
On Submit: Before Computation - Branching occurs before computations, validations, or processing. Use this option for buttons that do not need to invoke any processing (for example, a Cancel button).
On Submit: Before Validation - Branching occurs after computations, but before validations or processing. If a validation fails, page processing stops, a rollback is issued, and the page displays the error. Because of this default behavior, you do not need to create branches to accommodate validations. However, you may want to branch based on the result of a computation (for example, to a previous branch point).
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42. Branch Points (cont’d)
On Submit: Before Processing - Branching occurs after computations and validations, but before processing. Use this option to branch based on a validated session state, but before performing any page processing.
On Submit: After Processing - Branching occurs after computations, validations, and processing. This option branches to a URL or page after performing computations, validations, and processing. When using this option, remember to sequence your branches if you have multiple branches for a given branch point.
On Load: Before Header - Branching occurs before a page is rendered. This option displays another page instead of the current page or redirects the user to another URL or procedure.
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43. Adding Branch(es) Workflow
Open application
Open page to be edited
Click on Create Icon in Branches Section
Create Branch
Select branch point
Select branch type
Enter branch-type specific information/attributes
Specify condition(s) for display
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44. Processes
A page process is a unit of logic that performs an action at a specified point (i.e., when a specific event occurs) during the rendering or submission of the page.
From a functional perspective, there is no difference between page-level and application-level processes. The difference between these two process types is where the process is defined, that is at the page level or at the application level.
You create a process by running the Create Process Wizard. During the wizard, you define a process name, specify a sequence and the point at which the process will execute, and select a process category.
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45. Process Types Data Manipulation Close Popup Window
Data Manipulation process types are frequently used by wizards to support data manipulation language (DML) actions. Application Builder supports the following declarative data manipulation processes:
Select Automatic Row Fetch and Automatic Row Processing (DML) to create an automatic data manipulation language (DML) process.
Use Multi Row Update and Multi Row Delete in conjunction with tabular forms.
Use Add Rows to Tabular Form in conjunction with a tabular form.
Close Popup Window
Applies to processes running within a popup window. Upon execution, this process type closes the current popup window.
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46. Process Types (cont’d)
Form Pagination
Implements pagination through the detail records associated with a master detail form. Most often used in master detail forms (such as in the Master Detail Wizard), this process checks the master table to determine which set of detail records you are in and determines what the next detail record should be
On Demand
Creates an application-level process that can only be executed when called from a specific page. When you create this process type at the page-level, you are creating a reference to an existing application-level process.
PL/SQL
Runs the PL/SQL you provide. Use this process type to execute a block of PL/SQL entered directly into the process or to simply call an existing API or a stored procedure.
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47. Process Types (cont’d)
Reset Pagination
In Report regions, resets pagination back to the first result set. The Application Express engine keeps track of where the user is within a given result set. This process category returns the user to the beginning result set. In other words, this category resets the counters associated with the report region to return the first part of the result set the next time the result set displays.
Session State
Sets the values of existing session state items to null. Select this process type to clear the cache for applications, sessions, or items as well as to clear existing user
Web Services
Implements a Web Service as a process on a page. Running the process submits a request to the service provider.
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48. Process Points
You control when a process executes by specifying a sequence number and a process point under Process Point.
You can prevent a process from running during subsequent visits to a page by selecting one of the following options under Run Process:
Once for each page visit
Once for each session or when reset
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49. Adding Process(es) Workflow
Open application
Open page to be edited
Click on Create Icon in Processes Section
Create Process
Select process type
Select process point
Enter process-type specific information/attributes
Specify condition(s) for display
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50. Validations
Validations are used to verify the correctness of the data before page processing
You can define a validation declaratively by selecting a validation method.
If a validation fails, subsequent page processes or computations will not occur.
The validation you enter must be consistent with the validation type you selected.
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51. Validation Methods SQL PL/SQL
Compares item values to data in the database. For example, you can use a SQL validation to verify whether a last name typed into a field exists in the database. In the following Exists SQL validation, the field is named P1_LAST_NAME and the table is named customers.
SELECT 1 FROM customers WHERE last_name = :P1_LAST_NAME
PL/SQL
Useful if you need complex logic to validate entered data. For example, suppose you need to create a validation for an address form that requires the user to enter a province if the address is not in the United States. You could create the validation as a Function Returning Boolean, using the following PL/SQL:
BEGIN
IF :P1_COUNTRY = 'US' AND :P1_PROVINCE IS NULL THEN
RETURN FALSE;
ELSE
RETURN TRUE;
END IF; END;
You could also create the same validation implemented as a PL/SQL Expression as follows:
NOT (:P1_COUNTRY='US' AND :P1_PROVINCE IS NULL);
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52. Validations (cont’d) Item Level Null Item String Comparison
Checks if an item's value in session state is null. For example, you could validate that the user enters a value in a field by creating an item validation and then selecting the validation method Item Not Null.
Item String Comparison
Compares the value of an item to a specific string.
There are several string comparison validations that compare the value of an item to a literal string. For example, you select the validation type Item in Expression 1 is contained in Expression 2 to validate a user entry in a field against a list of values you provide. In Expression 1, enter the name of the item you want to validate without a colon, (e.g., :P1_VALUE). In Expression 2, enter a string of values you want to validate against.
Regular Expression
Regular expressions provide a method to describe text patterns.
Use a Regular Expression validation to perform data validation. For example, you could use the following regular expression validation to verify that a string of entered data always consists of groups of six numbers separated by commas and followed by a comma:
^([[:digit:]]{6},)+$
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53. Adding Validations Workflow
Open application
Open page to be edited
Click on Create Icon in Validations Section
Create Validation
Select validation level
Select validation method
Enter validation method specific information/attributes
Specify condition(s) for display
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54. Computations
Computations are used to assign a value to an identified item when a page is submitted or displayed.
Computations can be defined at application level or at page level.
Most application-level computations are performed for every page in an application
Page-level computations only execute when that page is rendered or processed
Similar to branches and processes, you can define a point at, (computation point), which the computation will be performed. This includes during page rendering or during page processing
If a computation fails, you can optionally define an error message.
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55. Click on Create Icon in Computations Section
Adding Computations Workflow
Open application
Open page to be edited
Click on Create Icon in Computations Section
Create Computation
Select computation level
Select computation item
Enter computation
Specify condition(s) for display
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