database instance: an independent database environment that runs on the cloud. A database instance contains multiple databases that are created by users and can be accessed by client tools and applications.
on-premises database instance: a database instance that is deployed in a non-cloud environment such as a data center.
ECS-based self-managed database: a self-managed database that is deployed on an Alibaba Cloud Elastic Compute Service (ECS) instance.
cluster: a collection of one or more database instances that run the same database engine, such as MySQL, Oracle, or SQL Server.
DBGateway: a daemon process that is deployed in the user environment. DBGateways collect and compute the performance data of databases, but do not read the business data of databases. DBGateways encrypt and compress data before they transmit data. For more information about DBGateways, see DBGateway.
index: a data structure that is used by the database management system to sort the data of one or more columns in a table. You can use indexes to quickly access specific data in a table.
immediate remediation suggestions: emergency measures to prioritize during system anomalies or performance failures, aimed at quickly restoring core business. These temporary optimizations or resource adjustments provide a buffer for permanent remediation solutions while minimizing impact on user experience and business.