Oracle Autonomous Database offers two deployment choices - Serverless or Dedicated.
With Autonomous Database Serverless, Oracle automates all aspect of the infrastructure and database management for customers including provisioning, configuring, monitoring, backing up and tuning. Users simply select what type of database they want (Data Warehouse or Transaction Processing), which region in the Oracle Cloud they want the database deployed, and the base compute and storage resources. Oracle automatically takes care of everything else for them. Once provisioned, the database can be instantly scaled either through the UI, APIs, or automatically based on the customers workload fully online.
Autonomous Database Dedicated allows customers to implement a Private Database Cloud running on dedicated Exadata Infrastructure within the Oracle Public Cloud. Making it an ideal platform to consolidate multiple databases regardless of their workload type or size or to offer database as a service within an enterprise. Dedicated infrastructure provides complete isolation from other tenants and provides an opportunity to customize operational policies, such as software update schedules, availability and density, to match your business requirements.
With Autonomous Database Dedicated, customers get their own Exadata infrastructure in the Oracle Cloud. The customers administrator simply specifies the size, region and availability domain where they want their dedicated Exadata infrastructure provisioned. They also get to determine the update or patching schedule if they wish. Oracle automatically manages all patching activity but with Autonomous Database Dedicated service, customers have the option to customize the patching schedule. You can specify which month every quarter you want, which week in that month, which day in that week and which patching window within that day. You can also dynamically change the scheduled patching date and time for a specific database if the originally scheduled time becomes inconvenient. The short video below shows exactly how to provision Dedicated Autonomous Exadata Infrastructure.
Once the Autonomous Exadata Infrastructure is provisioned the administrator can then partition the system into the desired number of clusters and or Container Databases (CDB). Each CDB can have a different update strategy, backup retention, availability and density. By default, only one CDB is necessary, and all user created database will be created within that container and inherit it’s update strategy, backup retention etc. The video below shows how easy it is to create an Autonomous Container Database.
Alternatively, the administrator can create separate CDBs for different lines of business or for different use cases. For example, one Container Database could be created as the TEST system to keep the test workload separate from production database. The TEST CDB would always be patched to the latest Release Update (RU) and wouldn’t have a standby database. While the WEB STORE CDB would contain production databases and would have a remote standby. It would also take a less aggressive patching strategy by using Release Update Revisions (RUR). The MANUFACTURING CDB would also house production database but since they belong to a different line of business, they will go into a separate CDBs.
Once the CDBs have been created, the system is now ready to provide database-as-a-service within the organization. Database users simply provision databases within the predefined CDBs. Just as with Serverless, database users only need to specify the base compute and storage resources and the databases can elastically grow or shrink fully online.
With Autonomous Database Dedicated (ADD), the level of security and performance isolated can be easily tailored for each workload. As we discussed earlier, you get Exadata Infrastructure fully dedicated to your use. The network path is through a VCN (virtual cloud network) and subnet defined by the Exadata infrastructure hosting the database. By default, this subnet is defined as private, meaning that there is no public Internet access to databases. This ensures only your company can access your Exadata Infrastructure and your databases.
Within each of your dedicated Exadata racks you can create further levels of isolation by creating separate clusters, and / or Container Databases (CDB). You can also isolate different workload by creating multiple Databases within each CBD.
As, I said before Oracle automatically provisions, configures, manages and monitors the Autonomous Database for you. But you have the opportunity with Autonomous Database Dedicated to customize the operational polices to best suit your business needs.
You can customize the software update / patching policy. For example, you can choice to deploy new software versions on your development and test databases first before you deploy it on production. You can also control when these updates are applied to prevent them from colliding with your peak business periods (quarter or year-end close, holiday season etc.).
Another possible level of customization is customizing the availability polices for different Container Databases (CDBs). For each CDB you can specify the level of availability and disaster recovery you need. You can also define the backup retention policy.
Finally, you can customize the level of over provisioning and peak usage polices for your database. For example, you can choose to over-provision your test databases but not your critical production databases.
Regardless of which Autonomous Database deployment you chose you will get the same great features, functionality, security and performance you have grown to expect from the Oracle Database.
For users that are simply looking for a database for a specific application or project and don't want to be involved in choosing any database details like versions, patching, etc., Serverless is right choice. Whereas users that want to rethink their I.T strategy and care about things like patching schedules, software versions, workload isolation, and want to be involved in choosing these, then Dedicated is the right choice.