How to Keep a Database Safe and Sound: The Database Administrator in Oracle 12c - dummies

How to Keep a Database Safe and Sound: The Database Administrator in Oracle 12c

By Chris Ruel, Michael Wessler

The person who installs and configures the Oracle 12c database, manages user access and accounts, ensures space for database objects, and (we hope) makes backups, among many other responsibilities, is the database administrator, or DBA.

Medium to large IT shops have one or more DBAs, sometimes even a large team of DBAs. Smaller IT shops may have a person working as a DBA part-time but doing system administration or application development as well. Regardless of whether you’re a full-time or part-time DBA, you need to understand the responsibilities and common tasks involved with the care and feeding of a database.

Try not to confuse the DBA with the application developer. The process of defining tables, columns, relationships, and rules is application design, data modeling, and ultimately application development. The DBA is peripherally involved with these tasks, but they’re typically the application developers’ responsibilities.

DBA responsibilities in Oracle 12c

A DBA has multiple responsibilities around which individual tasks are created to support. Work comes in the form of technical, non-technical, database-centric, and business-centric tasks, but they generally relate to a set of core areas. As a DBA, you have to

  • Protect the data. You are the gatekeeper and protector of the data you are entrusted to defend. Data must be protected from theft, damage, and destruction. Protecting the data encompasses both security and backup and recovery. This responsibility commonly comes in the form of establishing, testing, and monitoring backups and implementing security policies and technologies.

  • Provide access to the data. You must ensure that the data is available to those users and programs which are authorized to access it. Speedy, quick access is necessary because if a query takes too long to execute and the user gives up, it might as well never finish.

  • Data must be accessible as well; if the database is shutdown or otherwise unavailable, it does the users no good. Providing access to the data involves performance tuning and High Availability (HA).

  • Maintain the software. You are responsible for ensuring the general maintenance and housekeeping of the database is kept up to date. Databases must be monitored for errors, ensuring there is enough space to grow as new data is loaded, and monitor processing jobs for success.

    Furthermore, there is always a new version of software to upgrade to or apply a patch (often after hours). These are generally mundane items and much of it can be automated via scripts or Enterprise Manager, but they still are your responsibility.

  • Support the business. Databases do not exist in isolation. They are part of an overall business objective, and that business objective is usually evolving. New application code is being generated requiring developer assistance, audits of your processes are being conducted, and users always have miscellaneous issues.

    The most common example is applying a new application release to the database or implementing new technology to enable a new business capability. These efforts periodically correspond to database maintenance, but they are in support of moving the business objectives forward, and the wise DBA supports these efforts.

Common tasks for a DBA in Oracle 12c

Life as a DBA varies based on the nature of the business and the IT environment. Here’s how the core responsibilities can manifest themselves within a common task:

  • Protect the data by

    • Reviewing output logs and messages to ensure the previous night’s backups ran successfully.

    • Responding to questions about user access and database auditing procedures. (This task also falls under support the business.)

    • Researching and applying Critical Patch Update (CPU) patches to ensure security and vulnerability fixes are made. (This task also falls under maintain the software.)

  • Provide access to the data by checking Enterprise Manager and your cell phone texts for alerts showing down databases or listeners, which would impact user access to the databases.

  • Maintain the software by using Enterprise Manager and log files to search for database alerts, errors, and space usage threshold concerns.

  • Support the business by

    • Reviewing output logs and messages to ensure the previous night’s application batch jobs and processes completed.

    • Checking e-mail and responding to any application or user issues.

    • Applying application updates to development, test, and production databases to provide additional functionality and bug fixes for users.

Database administration is a respected profession in the IT field. Many people make a comfortable living as an Oracle DBA. Some would say Oracle wouldn’t be where it is today if not for the legions of dedicated Oracle professionals worldwide.