#This is demo about databases in containers

docker volume create pgdata

docker network create postgres

docker container run -d \
    -e POSTGRES_USER=postgres \
    -e POSTGRES_PASSWORD=postgres \
    -e POSTGRES_DB=postgres \
    -p 5432:5432 \
    -v pgdata:/var/lib/postgresql/data \
    --network postgres \
    --memory 512MB \
    --cpus 2 \
    --sysctl kernel.sem="250 32000 100 1024" \
    --sysctl kernel.shmmax=134217728 \
    --ulimit rtprio=99  \
    postgres

docker exec -it container_id bash

psql -U postgres 

CREATE DATABASE sample;

\c sample

CREATE TABLE users (
    users varchar(40),
    email varchar(40),
    data_reg date
);


INSERT INTO users VALUES (
    'fulano', 'fulano@fulano.org', now());

psql -U postgres sample

SELECT * FROM users;