$ yum update $ yum install postgresql noを選択する。すると下記の文字が現れる。 postgresql is available in Amazon Linux Extra topics "postgresql9.6" and "postgresql10" and "postgresql11" To use, run # sudo amazon-linux-extras install :topic: Learn more at https://aws.amazon.com/amazon-linux-2/faqs/#Amazon_Linux_Extras $ sudo amazon-linux-extras install postgresql9.6 $ sudo postgresql-setup initdb $ sudo systemctl sta