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.
There are three types of instances available in TencentDB for MySQL:
|Instance Type||Definition||Architecture||Visible in Instance List||Feature|
|Master instance||An instance that can be read from and written to||Yes||A master instance can mount read-only instances and disaster recovery instances for read/write separation and remote disaster recovery|
|Read-only instance||An instance that can only be read from||Single-node High IO Edition||Yes||A read-only instance cannot exist on its own; instead, it must be affiliated to a master instance. Its data comes solely from sync with the master instance. Besides, it must reside in the same region as the master instance|
|Disaster recovery instance||An instance that supports disaster recovery across AZs and regions||Yes||A disaster recovery instance is read-only during sync with a master instance. It can actively stop the sync and be promoted to a master instance for read/write access. It must reside in a different region from the master instance|