> The broad approach would be modify the existing pg_dump as little as
> possible; I am inclined to write the data as SQL (as currently done), and
> append an 'index' to the output, specifying the offset on the file that
> each piece of extractable data can be found. The 'restore' option would
> just go to the relevant section(s), and pipe the data to psql.
A problem I see with an index at file end is, that you will need to read the
file
twice, and that may be very undesireable if e.g the backup is on tape
or a compressed file.
I like your idea of uniquely formatted comments heading separate sections
of the dump file, if the "create table ..." is not already enough.
Andreas