Alibaba Cloud PolarDB is a cloud-native relational database service that separates computing resources from storage resources. The service provides three database engine editions: PolarDB for MySQL, PolarDB for PostgreSQL, and PolarDB for Xscale. PolarDB for MySQL offers full compatibility with MySQL and supports multiple primary nodes, active geo-redundancy for disaster recovery, and hybrid transactional/analytical processing (HTAP) capabilities. The service uses a shared-storage architecture where computing and storage resources are decoupled. PolarDB for PostgreSQL provides full compatibility with PostgreSQL and includes support for Alibaba Cloud's GanosBase engine and the PostGIS engine for spatio-temporal data processing. It is designed for building cloud-native applications or migrating traditional commercial databases to the cloud. PolarDB for Xscale (PolarDB-X) uses a distributed share-nothing architecture and is designed for MySQL-based applications requiring ultra-high concurrency. It provides high throughput, large storage capacity, low latency, and high scalability. The service offers auto scaling capabilities within seconds and supports storage capacity up to 500 TB. PolarDB is designed for business-critical database applications that require fast performance, high concurrency, and automatic scaling. Users can scale up node specifications and scale out the number of nodes in a cluster.