"Birchall, Austen" <austen(dot)birchall(at)metoffice(dot)gov(dot)uk> writes:
> If I do a
> pg_dump -Fc dbname -U postgres > backup.out
> to backup a database am I right to assume that any changes made to the database such as a row update that are made while the pg_dump is actually running will be captured in the resulting backup.out file?
No. You'll get a snapshot as of pg_dump's starting time.
There are some corner cases about DDL that's in progress while pg_dump
starts up, but user data will definitely adhere to the snapshot.
regards, tom lane