Data subscription helps obtain real-time incremental data of specific RDS instances. It is applicable for scenarios such as cache update, message notification, real-time data synchronization between heterogeneous data sources, and real-time data synchronization with complex ETL.
Key features of DTS subsciption include:
Obtain data changes from a RDS instance in a classic network.
Obtain data changes from a RDS instance in a VPC network.
The subscription object includes database and table. You can subscribe incremental data of selected tables as needed.
Incremental data is divided into DML (Data Manipulation Language) and DDL (Data Definition Language). You determine the specific data change type to be subscribed during configuration.
To subscribe data from a specific RDS instance, you must create a subscription channel (that is, the basic unit for data subscription) and allocate it to the RDS instance through the DTS console.
Upon creation, the subscription channel starts to capture incremental data from the source RDS instance, and stores the captured data locally. Consequently, you can use the DTS SDK to subscribe and consume incremental data from the subscription channel.
One subscription channel can be subscribed to only one downstream SDK. In the case that incremental data of one RDS instance is requested by multiple SDKs, you must create a corresponding subscription channel for each SDK. The subscription target of these channels are the same RDS instance.
Subscription channel displays different status on creation and progress.
|Channel status||Description||Operations available|
|Pre-checking||Subscription instance is performing pre-check.||
|Not started||Subscription channel has been configured, but not started.||
|Initializing||The subscription channel is initializing. The process may take up to 1 minute.||
|Normal||Subscription channel is running.||
|Abnormal||Subscription channel has encountered an issue.||
DTS subscription offers convenient design features such as:
Subscription object modification
You can add or delete the subscription object when the subscription channel is running.
Visualized subscription data
You can view the data in the subscription channel on the DTS console.
Consumption time modification
You can modify the consumption time of the subscription channel on the DTS console according to your requirements.
DTS monitors the performance of all tasks and detects problems, such as lag or abended processes. If a task fails, DTS immediately sends an alarm messages to the task owner.