Azure SQL Database Service Tiers

Azure SQL Database has four different service tiers which define the size, performance, features, and, most importantly, the cost of an Azure SQL Database. These service tiers are Basic, Standard, Premium, and Premium RS:

Note

The Database Transaction Unit is the measure of Azure SQL Database Performance. This is discussed later in the chapter.

Basic Service Tier

The Basic tier is the lowest tier available and is applicable to small, infrequently used applications, usually supporting one single active transaction at any given point in time.

The Basic tier has a size limit of 2 GB, a performance of 5 DTU, and costs $5/month:

Standard Service Tier

This is the most commonly used service tier and is best for web applications or workgroups with low to medium I/O performance requirements. Unlike the Basic service tier, it has four different performance levels: S0, S1, S2, and S3. Each performance level offers the same size (250 GB), however, they differ in terms...