Enterprise Manager Database Express (EM Express) provides a web-based interface for managing Oracle databases. In Oracle 19c, while DBCA automatically enables EM Express for the Container Database (CDB), Pluggable Databases (PDB) require manual configuration. This guide covers the complete setup process and explains how to switch between the modern Java JET interface and the feature-rich Flash-based UI.
Table of Contents
- 1. Overview of EM Express in Oracle 19c
- 2. Prerequisites
- 3. Configuring EM Express for CDB
- 4. Configuring EM Express for PDB
- 5. Java JET vs Flash-Based UI
- 6. Switching Between UI Modes
- 7. Best Practices
1. Overview of EM Express in Oracle 19c
Enterprise Manager Database Express is a lightweight, browser-based database management tool built into Oracle Database. Starting with Oracle 19c, the interface was modernized using Oracle JET (JavaScript Extension Toolkit), replacing the previous Flash-based implementation.
EM Express Architecture Overview
EM Express is a web-based management interface built into Oracle Database 19c that communicates through the XML DB HTTP listener on configurable HTTPS ports.
1 . Connect to the Database as SYSDBA
| Component | Description | Default Port |
| CDB EM Express | Manages the Container Database and common users | 5500 (HTTPS) |
| PDB EM Express | Manages individual Pluggable Database resources | 5501+ (HTTPS) |
| XML DB HTTP Listener | Handles web requests for EM Express | Configurable |
2. Prerequisites
Before configuring EM Express, ensure the following requirements are met:- Oracle Database 19c installed and running
- SYSDBA privileges for configuration tasks
- Network access to the configured HTTPS ports
- Modern browser with JavaScript enabled (Chrome, Firefox, Edge)
- Firewall rules configured to allow traffic on EM Express ports
3. Configuring EM Express for CDB
By default, DBCA configures EM Express for the CDB during database creation. However, you may need to verify or modify the configuration. Follow these steps to configure the HTTPS port for the Container Database.1 . Connect to the Database as SYSDBA
[oracle@dbserver ~]$ sqlplus / as sysdba SQL*Plus: Release 19.0.0.0.0 - Production on Tue Aug 11 13:31:02 2020 Version 19.8.0.0.0 Connected to: Oracle Database 19c Enterprise Edition Release 19.0.0.0.0 - Production Version 19.8.0.0.0
2. Verify Current Container Context
SQL> SHOW CON_NAME CON_NAME ------------------------------ CDB$ROOT
3. Check Existing HTTPS Port Configuration
SQL> SELECT DBMS_XDB_CONFIG.GETHTTPSPORT() FROM DUAL;
DBMS_XDB_CONFIG.GETHTTPSPORT()
------------------------------
0
A return value of 0 indicates that the HTTPS port is not configured.
SQL> SELECT DBMS_XDB_CONFIG.GETHTTPSPORT() FROM DUAL;
DBMS_XDB_CONFIG.GETHTTPSPORT()
------------------------------
0
A return value of 0 indicates that the HTTPS port is not configured.
4. Configure the HTTPS Port for CDB
SQL> EXEC DBMS_XDB_CONFIG.SETHTTPSPORT(5500); PL/SQL procedure successfully completed.
5. Verify the Configuration
SQL> SELECT DBMS_XDB_CONFIG.GETHTTPSPORT() FROM DUAL;
DBMS_XDB_CONFIG.GETHTTPSPORT()
------------------------------
5500
Access URL: CDB EM Express is now accessible at:
https://:5500/em
https://:5500/em
Figure 1: EM Express Login Screen – CDB
The EM Express login interface displays fields for Username, Password, and Container Name, with the Oracle Enterprise Manager Database Express branding.
1. List Available PDBs
The EM Express login interface displays fields for Username, Password, and Container Name, with the Oracle Enterprise Manager Database Express branding.
4. Configuring EM Express for PDB
Unlike the CDB, Pluggable Databases do not have EM Express enabled by default. Each PDB requires manual configuration with a unique HTTPS port.1. List Available PDBs
SQL> SHOW PDBS
CON_ID CON_NAME OPEN MODE RESTRICTED
---------- ------------------------------ ---------- ----------
2 PDB$SEED READ ONLY NO
3 WORAVRPDB1 READ WRITE NO
2. Switch to the Target PDB
SQL> ALTER SESSION SET CONTAINER = WORAVRPDB1; Session altered. SQL> SHOW CON_NAME CON_NAME ------------------------------ WORAVRPDB1
3. Verify Current HTTPS Port (Expected: 0)
SQL> SELECT DBMS_XDB_CONFIG.GETHTTPSPORT() FROM DUAL;
DBMS_XDB_CONFIG.GETHTTPSPORT()
------------------------------
0
4. Configure Unique HTTPS Port for PDB
SQL> EXEC DBMS_XDB_CONFIG.SETHTTPSPORT(5501);
PL/SQL procedure successfully completed.
5Confirm the Port Assignment
SQL> SELECT DBMS_XDB_CONFIG.GETHTTPSPORT() FROM DUAL;
DBMS_XDB_CONFIG.GETHTTPSPORT()
------------------------------
5501
Access URLPDB EM Express is now accessible at:
https://:5501/em
https://:5501/em
Figure 2: EM Express Login Screen – PDB
The PDB-specific EM Express login interface accessed via port 5501, showing the same authentication fields for pluggable database management.
Port Assignment Strategy for Multiple PDBs
| Container | Recommended Port | Access URL |
| CDB$ROOT | 5500 | https://hostname:5500/em |
| PDB1 | 5501 | https://hostname:5501/em |
| PDB2 | 5502 | https://hostname:5502/em |
| PDB3 | 5503 | https://hostname:5503/em |
- Java JET vs Flash-Based UI
Java JET UI (Default)
Oracle 19c+ Modern- Fast and responsive interface
- No Flash dependency
- Performance monitoring focus
- Limited administrative features
- No Server tab (user management)
Flash-Based UI (Legacy)
<span data-contrast="none" Pre-19c Style Feature-Rich- Full administrative capabilities
- User and schema management
- Storage administration
- Configuration options
- Complete Server tab access
Figure 3: Java JET UI – Database Home (Performance Tab Only)
The modern Java JET interface displays a simplified Database Home page with Status information (uptime, version, platform) and Performance graphs (Activity, Services, Instances). Only the Performance tab is available in this UI mode.
Figure 4: Flash-Based UI – Complete Administrative Interface
The legacy Flash-based UI provides full administrative capabilities with multiple tabs including Configuration, Storage, Security, and Performance. The interface displays comprehensive performance metrics, activity graphs, and complete database management options.
6. Switching Between UI Modes
Oracle provides a built-in script to toggle between the Java JET and Flash-based interfaces. This is particularly useful when you need access to administrative features not available in the modern UI.Switch to Flash-Based UI (EMX Mode)
SQL> @?/rdbms/admin/execemx emx Session altered. no rows selected old 1: select nvl( '&1','omx') p1 from dual new 1: select nvl( 'emx','omx') p1 from dual P1 --- emx PL/SQL procedure successfully completed. Session altered.
Important After running the script, log out and log back in to EM Express for the changes to take effect.
Revert to Java JET UI (OMX Mode)
SQL> @?/rdbms/admin/execemx omx Session altered. no rows selected old 1: select nvl( '&1','omx') p1 from dual new 1: select nvl( 'omx','omx') p1 from dual P1 --- omx PL/SQL procedure successfully completed. Session altered.
Quick Reference: UI Mode Commands
| Command | UI Mode | Description |
| @?/rdbms/admin/execemx emx | Flash-Based | Enable legacy UI with full features |
| @?/rdbms/admin/execemx omx | Java JET | Enable modern UI (default) |
7. Best Practices
Security Recommendations- Always use HTTPS (not HTTP) for EM Express connections
- Restrict network access to EM Express ports using firewall rules
- Use strong passwords for database accounts accessing EM Express
- Consider using a reverse proxy for additional security layers
Operational Guidelines
- Document port assignments for all CDBs and PDBs in your environment
- Use the Flash-based UI for administrative tasks requiring the Server tab
- Leverage the Java JET UI for day-to-day performance monitoring
- Verify port configurations after database cloning or migration
Troubleshooting Tips
| Issue | Resolution |
| Cannot access EM Express URL | Verify port configuration with GETHTTPSPORT() and check firewall rules |
| Server tab not visible | Switch to Flash-based UI using execemx emx |
| Port already in use | Choose a different port or identify the conflicting service |
| UI changes not reflected | Clear browser cache and log out/log in to EM Express |
For comprehensive information, refer to the official Oracle documentation:
Oracle 19c Database Administration Quick Start Guide