This Docker image will import all SQL files in a directory into PostgreSQL. It will also create all helper functions from postgis-vt-util for creating vector tiles.
docker run --rm \
    -v $(pwd):/sql \
    -e POSTGRES_USER="osm" \
    -e POSTGRES_PASSWORD="osm" \
    -e POSTGRES_HOST="127.0.0.1" \
    -e POSTGRES_DB="osm" \
    -e POSTGRES_PORT="5432" \
    openmaptiles/import-sql