Generating a dump file from PostgreSQL database inside a Docker container

Question

I am generating a dump file from a PostgreSQL database inside a Docker container which I want to be placed into the /tmp folder.

After opening a shell inside the Docker container, I then ran these commands:

sh-4.2# su - postgres
Last login: Wed Apr 18 05:22:26 UTC 2018 on pts/1
-bash-4.2$ psql
psql (9.3.15)
Type "help" for help.

I then executed this command to generate a dump file inside the /tmp folder:

postgres=# \! pg_dump -U user hidb -f /tmp/my_db_dumpa.sql;
Password: 

I gave the correct password when requested but there is no physical file inside /tmp folder in the host environment (Ubuntu Linux). Thanks

Answer 1

After running docker run su - postgres and use below command.

-bash-4.2$ pg_dump -U {username of the selected db} {dbname} -f /tmp/{file name whatever you want}.sql

next execute below to see this dump file generated or not

-bash-4.2$ cd /tmp/
-bash-4.2$ ls

once confirm

open another terminal and make sure docker is running and execute below commend to copy dump file into physical file in your desktop

sudo docker cp {docker name}:/tmp/{file name of the sql file} ~/

and goto home and verify weather your dump physical file generated or not