postgresql은 db 백업/복원으로 pg_dump라는 유틸리티를 제공함
pg_dump is a utility for backing up a PostgreSQL database. It makes consistent backups even if the database is being used concurrently. pg_dump does not block other users accessing the database (readers or writers).
pg_dump only dumps a single database. To backup global objects that are common to all databases in a cluster, such as roles and tablespaces, use pg_dumpall.
Dumps can be output in script or archive file formats. Script dumps are plain- text files containing the SQL commands required to reconstruct the database to the state it was in at the time it was saved. To restore from such a script, feed it to psql. Script files can be used to reconstruct the database even on other machines and other architectures; with some modifications, even on other SQL database products.