This section explains the terms related to RDS-PostgreSQL, which helps you better understand our products and facilitate your use.
1.1.1. What is an instance?
A database instance is the smallest management unit in RDS-PostgreSQL, which represents an independently run RDS You can create and manage instances of various database engines in an RDS system. For the series, specifications, engine, version, and status of the instances, see Instance Description.
1.1.2. What is an instance series?
The RDS-PostgreSQL instances are divided into single instances and primary/standby instances. For the instance specifications supported by different series, see Instance Specifications.
1.1.3. What are instance specifications?
For the various specifications of the RDS-PostgreSQL instances (number of vCPUs, memory (GB)), see the description of instance specifications. For database engines, see Database Versions.
1.1.4. What is an automatic backup?
When you create an instance, the RDS-PostgreSQL service enables the automatic backup policy by default. After the instance is created, you can modify it. The database instance automatically creates a full backup or an incremental backup based on your settings.
1.1.5. What is a manual backup?
A manual backup is a full backup of database instances initiated manually by the user, which is retained until the user deletes it manually.
1.1.6. Enterprise Project
Enterprise project permission is the basis for achieving fine-grained control. The cloud resources and enterprise members are managed according to enterprise projects. By binding the cloud resources and user groups with permissions through enterprise projects and authorizing user groups, users are restricted from using cloud resources in enterprise projects.
1.1.7. What are regions and AZs?
Regions and AZs are used to describe the location of a data center. You can create resources in a specific region and AZ.
• A region is a physical data center. Each region is completely independent, thus maximizing fault tolerance and stability. After a resource is created, its region cannot be changed.
• Availability Zone (AZ) refers to the physical area in which the power and network are independent of each other within the same region. One AZ is not affected by the faults of other AZs. A region can have multiple AZs, which are physically isolated but interconnected through the Intranet. This ensures the independence of the AZs and provides low-cost and low-latency network connections.
The following figure illustrates the relationship between regions and AZs.
Figure 1 Regions and AZs
