Which Azure SQL offering supports automatic database scaling and automatic pausing of the database during inactive periods?

The Azure SQL Database serverless compute tier is specifically designed for workloads with intermittent and unpredictable usage patterns. It automatically scales compute resources based on real-time workload demand. A key feature of the serverless tier is its ability to automatically pause the database during periods of inactivity. When paused, compute billing stops, and only storage is charged. The database automatically resumes when the next connection request is received. This combination of autoscaling and autopause provides significant cost optimization for suitable workloads.

A. Azure SQL Database Hyperscale: This tier is for very large databases (up to 100 TB) and offers rapid scaling of compute and storage, but it does not support automatic pausing.
B. Azure SQL managed instance: This is an "always-on" service designed for modernizing on-premises SQL Server applications. It does not have an automatic pausing feature.
D. Azure SQL Database elastic pool: Elastic pools allow multiple databases to share a set of resources for cost-effectiveness but do not support the automatic pausing of individual databases. ---

1. Microsoft Learn, Azure SQL Database Documentation. "Serverless compute tier for Azure SQL Database." This document states, "The serverless compute tier also automatically pauses databases during inactive periods when only storage is billed and automatically resumes databases when activity returns."

Reference: Introduction section, Paragraph 2.

2. Microsoft Learn, Azure SQL Database Documentation. "Compare vCore and DTU-based purchasing models of Azure SQL Database." This document includes a comparison table showing that "Auto-pause/resume" is a feature available only in the "Serverless" compute tier.

Reference: "Service Tiers" section, Feature comparison table.

3. Microsoft Learn, Azure SQL Managed Instance Documentation. "What is Azure SQL Managed Instance?." This document describes Managed Instance as a fully managed, "always-on" SQL Server Database Engine instance, which does not align with the concept of automatic pausing.

Reference: "Key features" section.