Part I — Understanding Oracle REST Data Services

1.1  What Is ORDS?

Oracle REST Data Services (ORDS) is Oracle’s Java-based middle tier that lets applications and external clients access Oracle Database through RESTful APIs over HTTP/HTTPS.

In short, ORDS acts as a bridge between a web or application client and Oracle Database.

Without ORDS

A traditional application connects directly to Oracle Database:

Application  →  Oracle Database

With ORDS

ORDS provides a REST-based layer in front of the database:

Web / Mobile / Application

↓ HTTP / HTTPS

ORDS

↓ SQL / PL/SQL

Oracle Database

For example, an application could call GET /ords/hr/employees. ORDS processes the request and returns the result as a REST response commonly JSON.

1.2  What Can ORDS Do?

ORDS can be used to:

• Expose Oracle data through REST APIs
• Execute SQL and PL/SQL through REST-enabled services
• Support web and mobile applications
• Provide the REST foundation used by Oracle APEX
• Support authentication and authorization mechanisms
• Integrate Oracle Database with external applications
• Support cloud and hybrid architectures

1.3  A Practical Example

Suppose your Oracle database has a table:

EMPLOYEES

  EMP_ID                NUMBER

  FIRST_NAME      VARCHAR2

  LAST_NAME       VARCHAR2

  SALARY                 NUMBER

  DEPARTMENT_ID   NUMBER

Instead of giving an external application direct database credentials, you can expose a controlled REST endpoint:

GET /ords/hr/employees

The application sends an HTTP request:

GET https://server.example.com/ords/hr/employees

ORDS communicates with Oracle Database, executes the appropriate SQL/PL/SQL logic, and returns the result:

Client

↓ HTTPS

ORDS

↓ JDBC

Oracle Database

↓ SQL / PL/SQL

Result set

1.4  ORDS vs. Oracle Database

A common misunderstanding: “Is ORDS another database?” — No. ORDS is a middle-tier service; your data remains in Oracle Database.

Think of it this way:

Component	Responsibility
Oracle Database	Stores and processes data
PL/SQL	Implements database-side business logic
ORDS	Exposes database functionality through REST
APEX	Provides low-code application development
Browser / Mobile App	Consumes the services

1.5  Why ORDS Matters for a DBA

ORDS changes how applications interact with Oracle Database. Instead of exposing database connectivity directly:

Application  →  Database

you can create a controlled API layer:

Application  →  ORDS  →  Database

This becomes particularly useful for APIs, integrations, Oracle APEX applications, mobile applications, ERP integrations, and cloud architectures.

Oracle REST Data Services (ORDS) is a Java-based tier that enables secure RESTful access to Oracle Database and its SQL/PL/SQL capabilities, over HTTP/HTTPS.

 

 

Part II — Installing ORDS on Oracle Database 19c

This walkthrough installs ORDS in Standalone Mode on Windows Server against an Oracle Database 19c target. Each step lists the exact commands to run and what to expect back.

Step 1 — Target Architecture

We will build this:

Windows Server

  ├─ Java 17

  ├─ Oracle Database 19c

  │    └─ ORDS Repository (metadata schema)

  ├─ ORDS Product (software)

  ├─ ORDS Configuration (–config directory)

  └─ ORDS Standalone

        └─ HTTP / HTTPS → Browser / Application

 

For this installation we will use ORDS Standalone Mode. Standalone Mode is excellent for learning, development, testing, and controlled environments. For production, you would normally put HTTPS and appropriate infrastructure in front of ORDS.

Step 2 — Prerequisites

Before installing ORDS, verify these components.

Database

Oracle Database: Oracle Database 19c. Check:

SELECT banner_full FROM v$version;

You should see Oracle Database 19c information. Also verify the listener:

lsnrctl status

Test the Oracle Database service:

tnsping ORCL

Replace ORCL with your actual Oracle Database service/TNS alias.

Step 3 — Install Java 17

Current ORDS documentation supports Java 17, 21, and 25. For this installation, use Java 17. After installation, open a Command Prompt:

java -version

You should see something similar to:

java version “17.x.x”

Then check:

where java

Step 4 — Configure JAVA_HOME

On Windows define JAVA_HOME. For example:

C:Program FilesJavajdk-17

Then add %JAVA_HOME%bin to the Windows PATH. Verify:

echo %JAVA_HOME%

java -version

Step 5 — Download Oracle ORDS

Download the ORDS distribution from Oracle’s official ORDS download page (“Oracle REST Data Services Downloads”). The downloaded file will have a name similar to:

ords-26.x.x.zip

The exact version changes over time, so do not hard-code an old version into your installation procedure.

Step 6 — Create the ORDS Directories

Separate the ORDS software from its configuration. For example:

C:ords

C:ords-config

Extract the ORDS ZIP into C:ords. You should have something like:

C:ords

  ├─ bin

  ├─ lib

  └─ …

The important directory is C:ordsbin. Oracle recommends keeping the configuration directory separate from the ORDS product directory, because this makes upgrades and maintenance easier.

Step 7 — Add ORDS to PATH

Add C:ordsbin to your Windows PATH. Open a Command Prompt and execute:

ords –help

If everything is correct, ORDS should display its command-line help. You can also check:

ords version

Step 8 — Verify Oracle Database Connectivity

Before installing ORDS, make sure the ORDS server can reach Oracle Database. For example:

Database Host : localhost

Listener Port : 1521

Service Name  : ORCL

Test:

sqlplus system@localhost:1521/ORCL

Then enter the password. If this connection works, ORDS should be able to reach Oracle Database using this connection information.

Step 9 — Decide Where ORDS Will Be Installed

This matters. If your Oracle Database 19c is configured as a container database with a pluggable database:

CDB

  └─ PDB

you normally install ORDS into the PDB, rather than treating the entire CDB like a traditional non-CDB Oracle Database. For example:

CDB: ORCLCDB

PDB: ORCLPDB

Check your environment:

SHOW CON_NAME;

SELECT name, open_mode FROM v$pdbs;

If you are using a PDB, switch to it:

ALTER SESSION SET CONTAINER=ORCLPDB;

Then verify with SHOW CON_NAME; it should return ORCLPDB. Oracle’s ORDS documentation has separate procedures for non-CDB/PDB installations and multitenant environments, so this distinction matters.

Step 10 — Create the ORDS Configuration Directory

Create:

mkdir C:ords-config

Tell ORDS to use this directory by specifying it explicitly:

ords –config C:ords-config install

This is the current ORDS installation syntax. Do not start a new installation with the old:

java -jar ords.war

Oracle now recommends the ORDS command-line interface.

Step 11 — Start the ORDS Installation

Run Command Prompt as an administrator/database installation account and execute:

ords –config C:ords-config install

ORDS will start asking installation questions, covered in the steps below.

Step 12 — Select the Database Connection Type

You will see options to select the Oracle Database connection type to use:

[1] Basic [2] TNS [3] Custom Oracle Database URL

For our example, select 1 (Basic Connection). You will then provide the Oracle Database host name, listener port, and service name. For example:

Host:    localhost

Port:    1521

Service: ORCLPDB

Use your own Oracle Database values.

Step 13 — Oracle Database Administrator Credentials

ORDS needs privileges to install its Oracle Database components. For a lab installation you can use:

Username: SYS

Role:     SYSDBA

Oracle also provides an ords_installer_privileges.sql script for when you want to use a dedicated installation account instead of SYS. The current documentation specifically describes this option for PDB installations.

Recommendation: For a lab installation, use SYS AS SYSDBA. Once the installation is working, build a controlled setup using a dedicated ORDS installer account.

Step 14 — The ORDS_PUBLIC_USER Account

During installation, ORDS configures its runtime user, ORDS_PUBLIC_USER. You may be prompted to:

[S] Specify your password [G] Generate password [C] Cancel

For a controlled environment, specify a password. Do not use a weak password such as “oracle” use a strong, unique password instead.

Step 15 — Tablespaces

You may see prompts for the default and temporary tablespaces. The default values are generally:

Default Tablespace : SYSAUX

Temporary          : TEMP

For a 19c installation you can generally accept SYSAUX and TEMP, unless your organization’s Oracle Database standards specify dedicated tablespaces.

Step 16 — Select Additional Features

Current ORDS releases provide options such as:

[1] Database Actions [2] REST Enabled SQL and Oracle Database API [3] REST Enabled SQL [4] Oracle Database API [5] None

Oracle’s current installer documentation lists Database Actions as the default option. For a learning environment, option [1] Database Actions is recommended, it gives you a complete ORDS environment to explore.

Step 17 — Configure Standalone Mode

ORDS can run in Standalone Mode. You may be asked:

Configure and start ORDS in Standalone Mode?

Choose:

Yes

For a lab installation this is the easiest way to validate the complete setup. Oracle documents Standalone Mode directly through the ORDS CLI and ords serve.

Step 18 — HTTP or HTTPS

You will typically see:

[1] HTTP [2] HTTPS

For a lab/test installation you can choose 1 and use port 8080, so your URL will be:

http://localhost:8080/ords/

Oracle documents 8080 as the default HTTP port and 8443 as the default HTTPS port.

Production recommendation: For production, HTTPS should always be used. Oracle specifically recommends HTTPS when running ORDS standalone.

Step 19 — Start ORDS

If you chose to configure and start Standalone Mode during installation, ORDS may start automatically:

ords –config C:ords-config serve

You should see startup messages indicating that ORDS is listening. For example:

INFO: Oracle REST Data Services initialized

INFO: HTTP listening on port 8080

Step 20 — Test ORDS

Open your browser:

http://localhost:8080/ords/

If ORDS is working, you should receive an ORDS response/page. You can also test this from another machine by replacing localhost with the ORDS server’s hostname or IP address, provided Windows Firewall and network configuration permit it.

Step 21 — Verify ORDS Database Objects

Connect to your Oracle 19c database:

SELECT username FROM dba_users

WHERE username LIKE ‘ORDS%’;

You should see users such as:

ORDS_METADATA

ORDS_PUBLIC_USER

You can also inspect:

SELECT username, account_status FROM dba_users

WHERE username IN (‘ORDS_METADATA’,’ORDS_PUBLIC_USER’);

Step 22 — Check the ORDS Version

From Windows:

ords version

This confirms the ORDS software version.

Step 23 — Check the ORDS Configuration

You can inspect the configuration using:

ords –config C:ords-config config list

The available configuration commands can be explored with:

ords config –help

Oracle recommends using the ORDS CLI for configuration management.

Step 24 — Test With a REST-Enabled Schema

Now we move from installation to Oracle Database REST services. Suppose we have:

CREATE USER RESTUSER IDENTIFIED BY “StrongPassword”;

Grant privileges according to your use case. Then REST-enable the schema:

BEGIN

  ORDS.ENABLE_SCHEMA(

    p_enabled             => TRUE,

    p_schema              => ‘RESTUSER’,

    p_url_mapping_type    => ‘BASE_PATH’,

    p_url_mapping_pattern => ‘restuser’,

    p_auto_rest_auth      => FALSE

  );

  COMMIT;

END;

/

The schema can now be accessed through an ORDS URL. Conceptually:

http://localhost:8080/ords/restuser/

Step 25 — Create a REST API

Create a simple table:

CREATE TABLE employees (

  employee_id   NUMBER PRIMARY KEY,

  employee_name VARCHAR2(100),

  department    VARCHAR2(100)

);

Insert sample data:

INSERT INTO employees VALUES (1, ‘Muhammad’, ‘IT’);

INSERT INTO employees VALUES (2, ‘Ahmed’, ‘Finance’);

COMMIT;

You can now expose this table through ORDS using REST definitions or AutoREST, depending on the API design you want. This is where ORDS becomes more interesting than just installing a web server.

Step 26 — Understand the Architecture

After you install ORDS, your environment looks like this:

Internet / LAN → Client (Browser / App)

↓ HTTP/S

ORDS  (port 8080 / 8443)

↓ JDBC

Oracle Database 19c

• ORDS_METADATA
• ORDS_PUBLIC_USER
• Application Schema (SQL / PL/SQL)

Understanding this architecture is essential before you start building REST APIs and Oracle APEX applications on top of ORDS.

Step 27 — Important Production Considerations

Installing ORDS successfully does not mean you have a production-ready environment. Before going to production, review the following areas:

Security

• HTTPS for ORDS
• Authentication and authorization
• Least-privilege database accounts
• Firewall rules
• Secrets and password management

Performance

• Connection pool sizing
• Database connection limits
• SQL performance
• JVM configuration
• Application workload

Availability

• Multiple ORDS instances
• Load balancing
• Database high availability
• Data Guard
• Backup and recovery

Monitoring

Monitor the full request path:

ORDS  →  JVM  →  Connection Pool  →  Oracle Database  →  SQL / PL/SQL

Step 28 — Common Installation Problems

Problem 1 — Java version

If you see an error that Java is too old, check:

java -version

Current ORDS releases require Java 17 or later.

Problem 2 — Database connection failure

Check:

lsnrctl status

tnsping ORCLPDB

sqlplus system@localhost:1521/ORCLPDB

Problem 3 — Wrong service name

Do not confuse SID with SERVICE_NAME. For a PDB, ORDS should normally connect using the PDB’s service.

Problem 4 — Database requests fail

Check the ORDS configuration, database connectivity, the ORDS_METADATA and ORDS_PUBLIC_USER accounts, and the connection pool.

Problem 5 — Port 8080 already in use

Check Windows:

netstat -ano | findstr :8080

If another service is using 8080, configure ORDS to use a different port.

Step 29 — Installation Checklist

At the end you should be able to confirm each of these:

• Oracle Database 19c is running
• Listener is running
• Java 17 is installed
• JAVA_HOME is configured
• ORDS is downloaded, extracted, and added to PATH
• A separate ORDS configuration directory is created
• Database connectivity is verified
• ORDS is installed in the database
• ORDS_METADATA is created and ORDS_PUBLIC_USER is configured
• Standalone Mode and HTTP/HTTPS are configured
• ORDS is started
• Browser/API connectivity is tested
• A REST-enabled schema is tested end to end

The Most Important Point

Do not think of an ORDS installation as “I installed ORDS and the service started.” Think of it as an architecture: Oracle Database 19c → ORDS → REST API → Application.

Once you understand that architecture, the next level becomes much easier:

Installation → Configuration → REST-Enabled Schema → REST Modules → REST Templates → REST Handlers → Authentication → Security → Production Deployment

• ORDS - Professional Edition
  Title: ORDS - Professional Edition