Instance types: this is vm size on which database will be running
Burstable: this is equivalent to t-series in ec2 instance
Memory optimized: these machines have more ram to cpu ration and it is r-series
Serverless: Here we will be charged per millisecond based on cpu and ram consumption (This option is enabled for aurora)
Standard classes
Cost Estimate
mysql
postgres
oracle
microsoft sql server
aurora mysql
aurora postgres
ibm db2
mysql db.m1.xlarge 4 cpu 15 GB RAM 100 GB mutli-az = 701 $
postgres db.m1.xlarge 4 cpu 15 GB RAM 100 GB multi-az = 782 $
oracle enterprise db.m5.xlarge 4 cpu 16 GB RAM 100 GB single-az = 310 $ + license costs
Sqlserver db.m5.xlarge 4 cpu 16 GB RAM 100 GB single-az = 449 $ + license costs
aurora mysql db.r3.xlarge 4 cpu 30.5 GB RAM 100 GB multi-az = 477.73 * number of nodes
aurora postgres db.r5.xlarge 4 cpu 30.5 GB RAM 100 GB multi-az = 477.73 * number of nodes
Storage: This uses disks i.e. ebs volumes, generally we have a general purpose volume and provisioned iops. Here we have an option for storage autoscaling which will automatically increase disk capacity till the maximum extent provided
Single-AZ Deployments
In this case your database will be created in one AZ from dbsubnet group.
The database created needs to handle both read and writes.
If this database fails, we need to recreate or restore
Muti-AZ Deployments
Multi AZ creates multiple db servers and supports automatic failover. the endpoint will not change post failover
Read Replica
AWS create a replication of database where only read is allowed.
This can be implemented with Single AZ as well as multi-az
Read replica can be created in other region as well.