How many deployment options do we have in Azure?
There are three options
1) SQL Virtual Machines - best for migrations and applications requiring OS-level access
2) Managed instances - best for most lift-and-shift migrations to the cloud
3) Databases - best for modern cloud applications. Hyperscale and server-less options are available
What is elastic database pool?
Allow us to share resources among multiple instances and databases and optimize your costs
Does elastic database pool support in all 3 deployment option?
No, its available for managed instance and database deployment options
What is SQL managed instance pools?
Its an elastic database pool in managed instance deployment option. It allow us to host many databases within a single set of provisioned SQL Database resources. This option is ideal for a software as a service (SaaS) application or provider because you can manage and monitor performance in a simplified way for many databases.
What is SQL database elastic pools?
Again its an elastic database pool used in SQL Database deployment option. It allow us to host multiple managed instances and share resources. Doing so can reduce overall deployment time to make migrations easier. You can also host smaller managed instances in an instance pool than you can in a single managed instance. This offer is currently in public preview.
What are all the SQL purchasing models available in Azure?
The Azure SQL purchasing model provides two options:
1) Based on virtual cores (vCore-based)
2) Based on database transaction units (DTU- based) (NOT available for Azure SQL Managed instance)
vCore-based model is recommended one as it allows us to independently select compute and storage resources.
How database transaction units (DTU) measured?
The DTU-based model is a bundled measure of compute, storage, and I/O resources.
In the vCore model, you pay for:
1) Compute resources. (The service tier + the number of vCores and the amount of memory + the generation of hardware.)
2) The type and amount of data and log storage.
3) Backup storage location. (Read-access geo-redundant storage (RA-GRS), Zone-redundant storage (ZRS), or locally-redundant storage (LRS)).
What is service tier?
DTU-based purchase model are differentiated by a range of compute sizes with a fixed amount of included storage, fixed retention period for backups, and fixed price and named as service tier
What are all the service tiers available in Azure to launch SQL?
1) General Purpose: Suitable for most business workloads. Offers budget-oriented, balanced, and scalable compute and storage options.
2) Business Critical: Suitable for business applications with low-latency response requirements. This tier is the only one that can use In-Memory OLTP to improve performance.
3) Hyperscale: Suitable for business workloads with highly scalable storage (100 TB+) and read-scale requirements. From a performance and cost perspective, this tier falls between General Purpose and Business Critical. Hyperscale is currently available only for single databases in Azure SQL Database.
What is Compute tier? (if you choose vCore model then have one more control to customize your cost)
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Provisioned compute - is meant for more regular usage patterns with higher average compute utilization over time, or for multiple databases that use elastic pools. Fixed price regardless of usage. We need to define sizing of compute resources for your workload.
Serverless compute - is meant for intermittent, unpredictable usage with lower average compute utilization over time. automatic compute scaling. billed only for the amount of compute used. Serverless also supports automatic pausing and resuming to help further price optimize. When your database is paused, you pay only for storage.
Hardware
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The default hardware generation at this time is referred to as Gen5 hardware. If you choose General Purpose within SQL Database and want to use the serverless compute tier, Gen5 hardware is currently the only option. It can currently scale up to 40 vCores. Fsv2-series (compute-optimized), M-series (memory-optimized), and DC-series (confidential computing) hardware options recently became available for SQL Database.
The purchasing model, service tier, and hardware selections you make will have a significant impact on the performance, availability, and cost of your deployment.
Management interfaces for Azure SQL
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1) Azure portal
2) SQL Server Management Studio
3) Azure Data Studio
4) CLI
Reference: https://docs.microsoft.com/en-in/learn/modules/azure-sql-intro/3-deployment-options
