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

To retrieve results directly in host, it is possible to run something like:

docker exec -i my_postgres_container psql -U postgres my_database \
--command "select id, name from my_table order by id desc limit 3;"
# returns:
 id   |   name   
-------+----------
 42921 | test-bd4
 42920 | test-bd4
 42919 | test-bd3
(3 rows)

and if you want a more readable output, using row_to_json SQL function and JSON query -> jq which should be installed on host, you can run :

docker exec -i my_postgres_container psql -U postgres my_database \
--command "select row_to_json(t) from (select * from my_table order by id desc limit 3) t;" \
 | grep '{"' | jq
# returns:
{
  "id": 42921,
  "name": "test-bd4",
  "created_at": "2023-03-22T18:20:29+01:00"
}
{
  "id": 42920,
  "name": "test-bd4",
  "created_at": "2023-03-22T18:20:29+01:00"
}
{
  "id": 42919,
  "name": "test-bd3",
  "created_at": "2023-03-22T18:20:29+01:00"
}

the grep command remove lines which are not in JSON

Answer 2

I had the same need but trying to run queries automatically when starting the server.

I achieved it using another service with the same image only to run those queries:

  database:
    container_name: database
    image: timescale/timescaledb-ha:pg15
    ports:
      - 5432:5432
    environment:
      POSTGRES_USER: "postgres"
      POSTGRES_PASSWORD: "postgres"
      POSTGRES_DB: "postgres"
    healthcheck:
      test: pg_isready -U postgres -d postgres
      interval: 3s
      timeout: 0s
      retries: 30

  database-start-scripts:
    container_name: database-start-scripts
    image: timescale/timescaledb-ha:pg15
    depends_on:
      database:
        condition: service_healthy
    # Some seeding
    command:
      - 'bash'
      - '-c'
      - |
        PGPASSWORD=postgres psql -h hiphiphip-database -p 5432 -U postgres postgres  <<SQL
          CREATE USER my_user WITH PASSWORD 'my_password';
          ALTER USER my_user WITH SUPERUSER;
          CREATE DATABASE my_db WITH OWNER my_user;
        SQL

Hoping this may help!

Answer 3

Without using an external terminal a person can run SQL commands within the container CLI.

psql -d [database-name] -U [username] -W

** Don't forget to replace [database-name] with your db-name & [username] with your actual username

Flags:

-d : Specify the database name you want to connect
-U : Specify the username as whom you want to connect
-W : Prompt for the password

Answer 4

In many common setups, the PostgreSQL port is published out to the host.

postgres:
  ports:
    - '12345:5432'

If this is the case, you don't need to do anything Docker-specific to connect to the database. You can use the psql client directly on your host system pointing to the first ports: number.

psql -h localhost -p 12345 -U project

This approach only requires psql or another ordinary PostgreSQL client be installed on the host and that the database container be configured with ports: making it accessible from outside Docker. (The ports: are not necessary for inter-container communication and a production-oriented setup could reasonably not have them.) This does not require the ability to run docker commands and the attendant security concerns, and it can avoid multiple layers of additional command quoting from a docker exec sh -c '...' sequence.

Answer 5

After the Postgres container is configured using docker, open the bash terminal using:

docker exec -it <containerID>(postgres container name / ID) bash

Switch to the Postgres user:

su - postgres

Then run:

psql

It will open the terminal access for the Postgres.

Answer 6

docker exec -it yiialkalmi_postgres_1 psql -U project -W 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 Tell psql that the user needs to be prompted for the password at connection time. This parameter is optional. Without this parameter, there is an extra connection attempt which will usually find out that a password is needed, see the PostgreSQL docs.

• project the database you want to connect to. There is no need for the -d parameter to mark it as the dbname when it is the first non-option argument, see the docs: -d "is equivalent to specifying dbname as the first non-option argument on the command line."

These are specified by you here

environment:
    POSTGRES_DB: project
    POSTGRES_USER: project
    POSTGRES_PASSWORD: project

Answer 7

If you need to restore the database in a container you can do this:

docker exec -i app_db_1 psql -U postgres < app_development.back

Don't forget to add -i.

:)

Answer 8

Just fired up a local test, not sure if -c is what you were after from the cli.

docker run -it --rm --name psql-test-connection -e PGPASSWORD=1234 postgres psql -h kubernetes.docker.internal -U awx -c "\conninfo"

You are connected to database "awx" as user "awx" on host "kubernetes.docker.internal" (address "192.168.65.4") at port "5432".

Answer 9

We can enter the container with a terminal sh or bash by using,

docker run -it <container id | name> <sh | bash>

if assume it is sh,

psql -U postgres

will work

Answer 10

This worked for me:

goto bash :

docker exec -it <container-name> bash

from bash :

psql -U <dataBaseUserName> <dataBaseName>

or just this one-liner :

docker exec -it  <container-name> psql -U <dataBaseUserName> <dataBaseName>

helps ?

Answer 11

You can enter inside the postgres container using docker-compose by typing the following

docker-compose exec postgres bash

knowing that postgres is the name of the service. Replace it with the name of the Postgresql service in you docker-compose file.

if you have many docker-compose files, you have to add the specific docker-compose.yml file you want to execute the command with. Use the following commnand instead.

docker-compose -f < specific docker-compose.yml> exec postgres bash

For example if you want to run the command with a docker-compose file called local.yml, here the command will be

docker-compose -f local.yml exec postgres bash

Then, use psql command and specify the database name with the -d flag and the username with the -U flag

psql -U <database username you want to connect with> -d <database name>

Baammm!!!!! you are in.

Answer 12

RUN /etc/init.d/postgresql start &&\
    psql --command "CREATE USER docker WITH SUPERUSER PASSWORD 'docker';" &&\
    createdb -O docker docker &&\

Answer 13

If you have running "postgres" container:

docker run -it --rm --link postgres:postgres postgres:9.6 sh -c "exec psql -h \$POSTGRES_PORT_5432_TCP_ADDR -p \$POSTGRES_PORT_5432_TCP_PORT -U postgres"