Introduction to Always Free Autonomous Database

.What is an autonomous database? 

An autonomous database is a modern cloud database from Oracle, which runs on the EXADATA infrastructure with a fully automatic database and data center operations. It uses machine learning and other AI techniques to automate all the work traditionally done by a database administrator. It is the world's first fully automated database defined on the principle of *3S*:

• Self-driving: Automates database and infrastructure management like provisioning, scaling, patching, backup, and so on. It also includes performance tuning and monitoring tasks. 
• Self-securing: Protects itself from all internal and external threats and has automatic encryption of all the data in rest or transit. It applies security updates with no downtime. 
• Self-repairing: Automatically recovers any failure and minimizes downtime with an SLA of 99.95%.

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Autonomous database types 

There are two types of autonomous databases based on the workloads:

• Autonomous data warehouse (ADW): Optimized for analytic workloads such as data warehouse, reporting databases, large data scan operations, data marts, and so on, this performs various BI activities and manages all database life cycle operations.
• Autonomous Transaction Processing (ATP): Optimized for transaction processing or mixed workload environments, this enables you to use real-time analytics, a high volume of random data access, and application development, and so on.

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The following image shows the difference based on the optimization of a specific workload:

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Deployment options for autonomous databases

The following deployment options are available for autonomous databases:

• Serverless deployment:  Uses a shared cloud infrastructure resources model.
• Dedicated deployment Allows the user to deploy an autonomous database within a dedicated cloud infrastructure.

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Always Free Autonomous Database details

You can provision up to two Always Free Autonomous Databases in the home region of our tenancy. Oracle provides these databases free of charge, and they're available for both paid and non-paid accounts.

Always Free Autonomous Database Specifications

• Processor: 1 Oracle CPU processor.
• Memory: 8 GB RAM
• Storage: 20 GB.
• Workload Type: Transaction processing or data warehouse 
• Database Version: Oracle Database 19c
• Infrastructure Type: Shared Exadata infrastructure
• Maximum Database Sessions: 20
• No scaling option for CPU and storage.
• If your Always Free Autonomous Database has no activity for seven consecutive days, the Database service stops automatically. You can restart the database to start using it again.
• If the Free Database remains stopped for three consecutive months, the database automatically terminates.
• You can configure events and notifications to stay Informed about Inactive Always Free Autonomous Databases.

For details, see Overview of the Always Free Autonomous Database 

Set up an Always Free Autonomous Database

Use the following steps to set up an Always Free Autonomous Database:

1. Log in to the Oracle Cloud Infrastructure [free tier service and create an account](https://www.oracle.com/cloud/free/ ).
2. Log in to the Oracle Cloud Infrastructure (OCI) console.

3. Select database type ATP or ADW.
4. Enter the compartment name, display name, and database name.

5. Select Shared Infrastructure

6. Make sure you select the Always Free option to enable it. 

 7. Create an administrator password

 8. Select the license included, and you can also configure access control rules.

Click Create to start provisioning the database.

 10. After three to four minutes, the green box displays, and the database is provisioned and available for use.

11. You have multiple options available to connect the database. Click the service console and log in with the administrator password. 

12. Select SQL developer web, a browser-based tool, to connect to the database.