how to install DB and others

InstallDB2Ubuntu.md

Install DB

PostgreSQL

sudo apt install postgresql libpq-dev

# set postgreSQL
# make admin
sudo -u postgres createuser admin -s
# login postgresql with admin
sudo -u postgres psql

# in postgresql
\password admin
\q

# login posgresql
rails dbconsole

update psql upto 12.0 for ubuntu18.04

# add repositry
## make /etc/apt/sources.list.d/pgdg.list
## write repositry
sudo sh -c 'echo "deb http://apt.postgresql.org/pub/repos/apt/ $(lsb_release -cs)-pgdg main" > /etc/apt/sources.list.d/pgdg.list

## add certification key
sudo apt install curl ca-certificates
curl https://www.postgresql.org/media/keys/ACCC4CF8.asc | sudo apt-key add -

# update repositry
sudo apt update && sudo apt upgrade

# install
sudo apt install postgresql-12

# confirmation
sudo su - postgres
## inner psql
psql
-> psql (12.0 (Ubuntu 12.0-2.pgdg18.04+1))

MySQL

sudo apt -y install mysql-server libmysqlclient-dev
# set password
sudo mysql_secure_installation

# inner mysql
ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY 'TegetegePassword';
flush privileges;

Heroku

sudo snap install heroku --classic
heroku login --interactive