Using multiple databases with the official PostgreSQL Docker image
The official recommendation for creating multiple databases is as follows:
If you would like to do additional initialization in an image derived from
this one, add one or more *.sql, *.sql.gz, or *.sh scripts under
/docker-entrypoint-initdb.d (creating the directory if necessary). After the
entrypoint calls initdb to create the default postgres user and database,
it will run any *.sql files and source any *.sh scripts found in that
directory to do further initialization before starting the service.
This directory contains a script to create multiple databases using that mechanism.
Usage
By mounting a volume
Clone the repository, mount its directory as a volume into
/docker-entrypoint-initdb.d and declare database names separated by commas in
POSTGRES_MULTIPLE_DATABASES environment variable as follows
(docker-compose syntax):
myapp-postgresql:
image: postgres:9.6.2
volumes:
- ../docker-postgresql-multiple-databases:/docker-entrypoint-initdb.d
environment:
- POSTGRES_MULTIPLE_DATABASES=db1,db2
- POSTGRES_USER=myapp
- POSTGRES_PASSWORD=
By building a custom image
Clone the repository, build and push the image to your Docker repository, for example for Google Private Repository do the following:
docker build --tag=eu.gcr.io/your-project/postgres-multi-db .
gcloud docker -- push eu.gcr.io/your-project/postgres-multi-db
You still need to pass the POSTGRES_MULTIPLE_DATABASES environment variable
to the container:
myapp-postgresql:
image: eu.gcr.io/your-project/postgres-multi-db
environment:
- POSTGRES_MULTIPLE_DATABASES=db1,db2
- POSTGRES_USER=myapp
- POSTGRES_PASSWORD=
Non-standard database names
If you need to use non-standard database names (hyphens, uppercase letters etc), quote them in POSTGRES_MULTIPLE_DATABASES:
environment:
- POSTGRES_MULTIPLE_DATABASES="test-db-1","test-db-2"