I work a lot in postgres and I find pg_dump to be a useful command, since I can call it in a cronjob.

http://www.postgresql.org/docs/current/static/app-pgdump.html

I don't think it accepts the Where clause.

An alternative would be to run a command like this:

psql mydb -c "select * from C_order where period=2009 and org<>'A'"
[download]

And then you'll have output you could save. Look up the psql command's options, it will probably let you make the output more useful for your backup policy.

HTH,
SSF