What is Azure SQL Database

• Fully managed SQL Database (single database or pool of databases) in Azure cloud
• PaaS - Fully managed platform-as-a-service
• Always running the latest version of SQL Server
• Flexible pricing model
  • vCores
  • DTU’s
• Single database or Elastic Pool
• Automatic scaling
• Service tiers for different workloads
  • Standard (general purpose)
  • Premium (for applications with high transaction rates)
  • Hyper-scale (very large transactional databases)
• https://docs.microsoft.com/en-us/azure/azure-sql/database/sql-database-paas-overview
• https://docs.microsoft.com/en-us/azure/azure-sql/database/elastic-pool-overview

When to use?

• When syncing on-premise database is needed to sync to Azure
  • syncing: one-way (on-premise -> Azure) or two-way (on-premise <-> Azure)
  • Cloud migration where both on-premise and Azure needs data during migration phase
• Modern apllications (for which single database is ok)
• Multi-tenancy
  • For applications, in which each user requires thier seperate database
  • Although ‘each user requires thier seperate database’ but still a silgle database is required for one user
  • So, there will be pool of “Single SQL Databases” (one database for each user) where databases is isolated from each other

Concepts

• Server: Microsoft SQL server
  • When creating Azure SQL Database, you must create server first on which SQL database will run
  • When using “Azure SQL Database” template in Azure portal, you will get a Server and a Database
• Database: Single SQL server database
• Elastic pool: Pool of SQL server databases

Elastic Pool

What is it?

• SQL Database elastic pool is a shared resource model that enables higher resource utilisation efficiency, with all the databases within an elastic pool sharing predefined resources within the same pool
• The workload pattern is well defined and is highly cost-effective in multitenant scenarios
• Elastic pools in Azure SQL Database enable SaaS developers to optimize the price performance for a group of databases
• See: https://docs.microsoft.com/en-us/azure/azure-sql/database/elastic-pool-overview

When to use?

• Multi-tenant apllications
• Elastic databases are useful when you have several databases and you want to monitor and manage all the databases at the same time

Next

• Creating Database Server
• Creating Single Database
• Creating Elastic Pool