Cannot recreate database instance due to `create_before_destroy` set to `true` on the cluster instance

[nitrocode]

Describe the Bug

Hi all.

The use-cases where the database has to be recreated from a snapshot, results in an error due to a conflicting name.

I noticed that create_before_destroy = true is on both of these resources

aws_rds_cluster_instance
aws_rds_cluster_parameter_group
aws_db_parameter_group

The second aws_rds_cluster_parameter_group and third aws_db_parameter_group ones correctly has the option to either use name or name_prefix which can avoid the recreation issue, but the first aws_rds_cluster_instance only uses identifier without an option to use identifier_prefix.

https://github.com/cloudposse/terraform-aws-rds-cluster/blob/d13a56c866b80a155c052f2bb7a870e4fe1992a4/main.tf#L349-L351

https://github.com/cloudposse/terraform-aws-rds-cluster/blob/d13a56c866b80a155c052f2bb7a870e4fe1992a4/main.tf#L404-L408

https://github.com/cloudposse/terraform-aws-rds-cluster/blob/d13a56c866b80a155c052f2bb7a870e4fe1992a4/main.tf#L429-L433

Even if the flag identifier_prefix was set to presumably avoid this naming conflict issue, the flag create_before_destroy = true for these resources doesn't make sense to me since if the old database was going to be destroyed, creating a brand new one wouldn't prevent an outage. Is this flag really providing value?

Two ways to solve this and both solutions could also be employed

• Provide an option to use identifier_prefix for aws_rds_cluster_instance
• Remove create_before_destroy = true flag for these resources

Expected Behavior

Recreation without naming conflict

Steps to Reproduce

1. terraform apply an empty database
2. provide the snapshot identifier arn which will result in a recreation
3. terraform apply

You should see the error now

Screenshots

N/A

Environment

terraform 1.11.0 module v1.18.0

Additional Context

• https://github.com/cloudposse/terraform-aws-rds-cluster/pull/213
• Docs regarding the create_before_destroy flag for aws_db_parameter_group and there is no equivalent for aws_rds_cluster_instance but one can predict if there was, it would most likely recommend identifier_prefix.