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Introducing Oracle Application Express

Could your organization be more agile, developing applications faster, cheaper, and more efficiently? Consider using Oracle® Application Express (APEX) and low-code development—a visual development method using drag-and-drop elements.

Introduction

APEX enables you to adapt to changing requirements and empowers developers and your entire organization to be a part of the solution quickly.

Introducing Oracle Application Express

Image source: https://apex.oracle.com/en/

Why APEX?

APEX is the easiest way for developers to build visually appealing apps for their data. APEX has the following features:

  • Simple: The Application Builder’s intuitive, browser-based GUI interface takes you step-by-step through creating your applications. You can easily learn to use APEX, and the robust components let you add high-level functionality with limited code. Your customers can become productive in less than a week.

  • Powerful: Use APEX to create simple web versions of spreadsheets to complex, mission-critical applications used to tens of thousands of users daily.

  • Proven: APEX successfully has powered thousands of applications globally for many years.

  • Secure: By design, APEX builds highly secure, out-of-the-box web applications. As standards for security and the web evolve and hackers get more resourceful, the APEX focus on security ensures that your applications have state-of-the-art protection.

  • Portable: APEX runs wherever you have Oracle Database, whether on-premises or in the cloud. You can easily deploy APEX to any environment.

Architecture

The Oracle APEX Architecture document describes the APEX architecture clearly and succinctly. This section contains the first part of that document.

Overview

Oracle APEX uses a simple three-tier architecture where requests are sent from the browser, through a web server and then finally to the database. APEX executes all processing, data manipulation, and business logic in the database. This architecture guarantees zero-latency data access, top performance, and scalability.

When a user submits a page from APEX, the process flows from the page through Oracle REST Data Services (ORDS) to APEX and back again, as shown in the following image.

Introducing Oracle Application Express

Image source: https://apex.oracle.com/en/platform/architecture/

APEX sends a web request from the web browser to Oracle REST Data Services (ORDS), where it is sent to Oracle Database to be actioned. Within the database, APEX processes the request. After the processing completes, the result is sent back through ORDS to the browser.

The Oracle RAD stack

The Oracle RAD stack is an inclusive technology stack based on three core components: Oracle REST Data Services (ORDS), Oracle APEX, and Oracle Database.

This stack provides all the necessary components to develop and deploy world-class, powerful, beautiful, and scalable apps. There are no other moving parts of the additional components required. In addition, both Oracle APEX and ORDS are free of cost features of Oracle Database, meaning if you have Oracle Database, you already have this Oracle RAD stack.

REST data services (ORDS)

Introducing Oracle Application Express ORDS is a Java application that enables developers with SQL and database skills to develop REST APIs for Oracle Database, Oracle Database 12c JSON Document store, and the Oracle NoSQL Database.

APEX

Introducing Oracle Application Express The Oracle Database’s native low-code development platform enables you to build stunning, scalable, secure apps, with world-class features, that can be deployed anywhere.

Database

Introducing Oracle Application Express Oracle Database—the most complete, integrated, and secure database solution for any scale deployment. This solid foundation enables apps built using Oracle APEX to be enterprise ready from day one.

Install APEX 18.1

The following section comes from https://oracledbwr.com/install-oracle-apex-18-1-on-premises-windows-18-3-0-database-using-oracle-http-server-12-1-3-0-0/.

Installation prerequisites

Oracle Application Express release 18.1 requires an Oracle Database release 11.2.0.4 or later, including Enterprise Edition and Express Edition (Oracle Database XE).

Download APEX 18.1 software here and click Accept.

Introducing Oracle Application Express

Step 1: Unzip the APEX 18.1.0.00.45 software

unzip apex_18.1.zip -d /oradb/

Step 2: Create a new APEX tablespace

CREATE TABLESPACE APEX DATAFILE ‘/oradb/app/oracle/oradata/clone/apex01.dbf’ SIZE 1G;

Step 3: Check the APEX installation

SELECT comp_name, version, status FROM dba_registry WHERE comp_id=’APEX';
no rows selected

Step 4: Start the APEX 18.1 installation

SQL> @apexins APEX APEX TEMP /i/
Where:
 apex_tbs – name of the tablespace for the APEX user.
 apex_files_tbs – name of the tablespace for APEX files user.
 temp_tbs – name of the temporary tablespace.
 images – virtual directory for APEX images. Define the virtual image directory as /i/ for future updates. */

The preceding script creates a few schemas on the database.

Use the following command to test by querying the ALL_USERS view:

SQL> select username,created from all_users where USERNAME like ‘%APEX%’;

USERNAME                      CREATED
———————                       ——————-
APEX_PUBLIC_USER             29-MAY-18
APEX_180100                  29-MAY-18
APEX_INSTANCE_ADMIN_USER     29-MAY-18

Step 5: Check the version and status of the installation

SELECT comp_name, version, status FROM dba_registry WHERE comp_id=’APEX';

COMP_NAME                       VERSION          STATUS
—————                           ——————           ———-
Oracle Application Express     18.1.0.00.45       VALID

Step 6: Check the APEX RELEASE VERSION

select * from apex_release;

VERSION_NO            API_COMPAT      PATCH_APPL
———-                  ———-            ———————
18.1.0.00.45          2018.04.04      APPLIED

Step 7: Run the Embedded PL/SQL Gateway configuration (EPG)

This step begins the APEX configuration.

The following script loads the APEX images into XDB:

 @apex_epg_config.sql <parent of apex directory>

 SQL> @apex_epg_config.sql /oradb

Step 8: Make sure that specific accounts are unlocked

The step continues the APEX configuration.

ALTER USER anonymous ACCOUNT UNLOCK;
ALTER USER xdb ACCOUNT UNLOCK;
ALTER USER apex_public_user ACCOUNT UNLOCK;
ALTER USER flows_files ACCOUNT UNLOCK;

Step 9: Configure database parameters for APEX

The step continues the APEX configuration.

SHOW PARAMETER job_queue_processes

NAME                        TYPE           VALUE
———                         —————          ———–
job_queue_processes         integer        4000

SHOW PARAMETER shared_servers

NAME                        TYPE           VALUE
————                        ————           ———–
max_shared_servers          integer
shared_servers              integer        1

Change the shared_servers parameter:

ALTER system SET shared_servers=5 scope=both;

Step 10: Set the XDB HTTP listener port and APEX ADMIN password.

The step completes the APEX configuration.

For users, you can use ADMIN by default, and skip the email. Also, you can change the HTTP port. However, the default port is 8080.

SQL>@/oradb/apex/apxconf.sql

PORT
———-
8080

Enter the values for the XDB HTTP listener port and the password for the APEX ADMIN user. The default values are in brackets [ ]. Press Enter to accept the default value.

Use this script to change an APEX instance administrator’s password. If the user does not yet exist, the script creates one.

Enter the administrator's username [ADMIN]
User "ADMIN" does not yet exist and will be created.
Enter the ADMIN's email [ADMIN]
Enter the ADMIN's password []
Created instance administrator ADMIN.
Enter a port for the XDB HTTP listener [ 8080]
…changing HTTP Port
APEX configuration finishes.

Step 11: Check the HTTP port

SQL> select dbms_xdb.gethttpport from dual;

GETHTTPPORT
———–
8080

Step 12: Check the listener status and HTTP port is enabled

[oracle@clone:apex clone] lsnrctl status

LSNRCTL for Linux: Version 12.2.0.1.0 – Production on 29-MAY-2018 19:20:08
Copyright (c) 1991, 2016, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=clone.localdomain.com)(PORT=1521)))

STATUS of the LISTENER
————————
Alias LISTENER
Version TNSLSNR for Linux: Version 12.2.0.1.0 – Production
Start Date 25-MAY-2018 21:52:41
Uptime 3 days 21 hr. 27 min. 26 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Parameter File /oradb/app/oracle/product/12.2.0.1/db_1/network/admin/listener.ora
Listener Log File /oradb/app/oracle/diag/tnslsnr/clone/listener/alert/log.xml
Listening Endpoints Summary…
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=clone.localdomain.com)(PORT=1521)))
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcps)(HOST=clone.localdomain.com)(PORT=5500))(Security=(my_wallet_directory=/oradb/app/oracle/admin/CLONE/xdb_wallet))(Presentation=HTTP)(Session=RAW))
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=clone.localdomain.com)(PORT=8080))(Presentation=HTTP)(Session=RAW))
Services Summary…
Service “CLONE.localdomain.com” has one instance.
Instance "clone", status READY, has one handler for this service…
Service "cloneXDB.localdomain.com" has one instance.
Instance "clone", status READY, has one handler for this service…
The command completed successfully

Step 13: Log in to the Administration Services login page

In the browser, log in as an ADMIN user to the Administration Services login page: https://clone.localdomain.com:8080/apex/apex_admin.

Conclusion

Oracle APEX is the right tool if you want to build applications that function better, perform, better, and deliver a better end-user experience. It dramatically simplifies enterprise application development and deployment. Based on the information in this post, choosing Oracle APEX probably makes sense for your next development project.

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