Error: Invalid attribute name

│ Error: Invalid attribute name
│
│   on main.tf line 15, in resource "aws_db_instance" "my_mariadb_instance":
│   15:   db_subnet_group_name =  "${module.vpc.public_subnets.[1]}"
│
│ An attribute name is required after a dot.
╵
Solution:
 db_subnet_group_name =  "${module.vpc.public_subnets.1}"

See also

• terraform plan: [ -refresh-only | -lock=false | -target | -var-file | will be created | --help], Terraform plan errors, Terraform plan examples, Terraform plan execution errors, (known after apply)