Docker - How can run the psql command in the postgres container?

Question

I would like to use the psql in the postgres image in order to run some queries on the database. But unfortunately when I attach to the postgres container, I got that error the psql command is not found...

For me a little bit it is a mystery how I can run postgre sql queries or commands in the container.

How run the psql command in the postgres container? (I am a new guy in Docker world)

I use Ubuntu as a host machine, and I did not install the postgres on the host machine, I use the postgres container instead.

docker-compose ps
        Name                       Command               State               Ports            
---------------------------------------------------------------------------------------------
yiialkalmi_app_1        /bin/bash                        Exit 0                               
yiialkalmi_nginx_1      nginx -g daemon off;             Up       443/tcp, 0.0.0.0:80->80/tcp 
yiialkalmi_php_1        php-fpm                          Up       9000/tcp                    
yiialkalmi_postgres_1   /docker-entrypoint.sh postgres   Up       5432/tcp                    
yiialkalmi_redis_1      docker-entrypoint.sh redis ...   Up       6379/tcp     

Here the containers:

docker ps
CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                         NAMES
315567db2dff        yiialkalmi_nginx    "nginx -g 'daemon off"   18 hours ago        Up 3 hours          0.0.0.0:80->80/tcp, 443/tcp   yiialkalmi_nginx_1
53577722df71        yiialkalmi_php      "php-fpm"                18 hours ago        Up 3 hours          9000/tcp                      yiialkalmi_php_1
40e39bd0329a        postgres:latest     "/docker-entrypoint.s"   18 hours ago        Up 3 hours          5432/tcp                      yiialkalmi_postgres_1
5cc47477b72d        redis:latest        "docker-entrypoint.sh"   19 hours ago        Up 3 hours          6379/tcp                      yiialkalmi_redis_1

And this is my docker-compose.yml:

app:
image: ubuntu:16.04
volumes:
    - .:/var/www/html

nginx:
    build: ./docker/nginx/
    ports:
        - 80:80
    links:
        - php
    volumes_from:
        - app
    volumes:
        - ./docker/nginx/conf.d:/etc/nginx/conf.d

php:
    build: ./docker/php/
    expose:
        - 9000
    links:
        - postgres
        - redis
    volumes_from:
        - app

postgres:
    image: postgres:latest
    volumes:
        - /var/lib/postgres
    environment:
        POSTGRES_DB: project
        POSTGRES_USER: project
        POSTGRES_PASSWORD: project

redis:
    image: redis:latest
    expose:
        - 6379

Answer 1

docker exec -it yiialkalmi_postgres_1 psql -U project -W project project

Some explanation

• docker exec -it The command to run a command to a running container. The it flags open an interactive tty. Basically it will cause to attach to the terminal. If you wanted to open the bash terminal you can do this

docker exec -it yiialkalmi_postgres_1 bash

• yiialkalmi_postgres_1 The container name (you could use the container id instead, which in your case would be 40e39bd0329a)

• psql -U project -W project The command to execute to the running container

• U user

• W password
• project the database you want to connect to.

These are specified by you here

environment:
    POSTGRES_DB: project
    POSTGRES_USER: project
    POSTGRES_PASSWORD: project