A database instance is a standalone database environment running in Tencent Cloud. It can contain multiple user-created databases and can be accessed using the same tools and applications as those for a standalone database instance.
Tencent Cloud database MySQL has the following three database examples:
| Instance type | Definition | Instance Architecture | Whether the list of instances is visible | Feature |
|---|---|---|---|---|
| Root instance | A readable and writable instance | Yes | Master instance can mount read-only instances and disaster recovery instances to realize read/write separation and remote disaster preparedness functions. | |
| Read-only Instance | Only instances of read function are provided | Single node high IO version | Yes | A read-only instance cannot exist alone and must belong to a certain Master instance. The only data source is synchronizing data from Master instance, which can only be in the same region as the master instance. |
| DR Instance | Provide examples of disaster preparedness capabilities across availability zones and regions | High availability version | Yes | Disaster recovery instances can only be read when synchronized. Disaster recovery instances can be actively disconnected from Master instance and actively promoted to the main instance, which can provide the ability to read and write Access, which must be different from Master instance. |
