Update deprecated resources

Use the following steps to migrate from resources that have been deprecated or renamed without destroying existing resources.

tip

Backup your Terraform state file terraform.tfstate to use in the case of a rollback.

In the following example, the aiven_database field is migrated to the new aiven_pg_database field for an Aiven for PostgreSQL® service.

Replace references to the deprecated field with the new field. In the following file aiven_database was replaced with aiven_pg_database:

- resource "aiven_database" "mydatabase" {
    project       = aiven_project.myproject.project
    service_name  = aiven_pg.mypg.service_name
    database_name = "<DATABASE_NAME>"
}


+ resource "aiven_pg_database" "mydatabase" {
    project       = aiven_project.myproject.project
    service_name  = aiven_pg.mypg.service_name
    database_name = "<DATABASE_NAME>"
}

View a list of all resources in the state file:
```
terraform state list
```
Remove the resource from the control of Terraform:
```
terraform state rm <DEPRECATED_RESOURCE>
```
tip
Use the -dry-run flag to preview the changes without applying them.
Add the resource back to Terraform by importing it as a new resource:
```
terraform import <NEW_RESOURCE> project_name/service_name/db_name
```
Check that the import is going to run as you expect:
```
terraform plan
```
Apply the new configuration:
```
terraform apply
```