Mastering Oracle DBaaS with OEM12c: Step‑by‑Step Guide and Best Practices

On November 12, senior engineer Lin Jingxu delivered an online session for the DBA+ Beijing group, sharing practical knowledge on delivering Oracle Database‑as‑a‑Service (DBaaS) through the Oracle Enterprise Manager 12c (OEM12c) platform.

Required OEM12c Components

Enterprise Manager for Oracle Cloud

Enterprise Manager for Oracle

Consolidation Planning and Chargeback

Enterprise Manager for Oracle Virtualization

Enterprise Manager for Oracle Cloud Framework

Enterprise Manager for Oracle Database

Enterprise Manager for Storage Management

Enterprise Manager for Oracle Virtual Infrastructure

After installing OEM12c, the em_catalog.zip patch must be applied.

Why Customers Need Oracle DBaaS

Many Oracle‑heavy customers face challenges such as complex provisioning, inconsistent environments, and difficulty in scaling resources. DBaaS addresses these issues by offering self‑service deployment, pre‑packaged configurations, one‑click provisioning, on‑demand scalability, efficient resource utilization, clear metering, and rapid developer agility.

DBaaS Advantages

Self‑service database deployment and management

Pre‑packaged, pre‑configured database setups

One‑click provisioning

Elastic underlying platform

Optimized hardware and resource usage

Transparent metering and billing

Enterprise‑grade control for IT and development teams

Services Enabled by OEM12c

OEM12c provides a range of services for Oracle databases, illustrated in the accompanying diagram.

Oracle DBaaS Architecture

The overall architecture consists of the OEM12c management layer, the underlying compute/storage resources, and the DBaaS service endpoints.

Implementation Workflow

The DBaaS implementation follows a series of stages, from environment preparation to service request execution.

OEM12c Installation Process

The installation steps are captured in the following screenshots, showing the sequence of configuration screens.

Configuring PaaS and DB Pool

The PaaS configuration page and DB pool settings are illustrated below.

Database Pool Consistency

All databases within a pool must share the same operating system and version.

Profile Configuration

Profiles can be created for RMAN backups, DMP imports, or data‑only instances. The UI for profile creation is shown below.

Service Template Creation

Service templates can be applied to instances, schemas, or PDBs. After basic settings, the next step is to submit a service request to create the database.

If the default selection is not a database, the user must manually change it. Successful creation and failure messages (e.g., insufficient OS resources) are displayed in the UI.

Resource Allocation and Billing

When submitting a service request, users can define the database’s lifecycle, creation date, and retention period (e.g., a test database created on 2015‑12‑01 that lives for 20 days). Oracle’s public cloud offers temporary databases that expire automatically.

Resource quotas such as 4 GB memory, 50 GB storage, and 60 % CPU can be enforced, and weighted cost calculations can be applied. Although Oracle does not provide a built‑in billing engine, it exposes APIs to extract usage data, enabling developers to build custom charge‑back systems.

Typical billable items include CPU usage (charged per unit per day), memory, and storage consumption, as illustrated in the billing diagram.

Customizing the OEM12c Login UI

Enterprises can replace the default Oracle logo and branding on the OEM12c login page using the emcli command. Images must meet size constraints (pixel dimensions). The following screenshots show a customized login screen without any Oracle branding.

Conclusion

The session demonstrated a complete, end‑to‑end process for provisioning Oracle databases as a cloud service using OEM12c, covering component selection, installation, configuration, resource governance, and UI customization, providing a practical reference for DBAs and cloud architects.