Thom Brown <t...@linux.com> writes: > Can I ask why it doesn't return the same snapshot ID each time? > Surely it can't change since you can only export the snapshot of a > serializable or repeatable read transaction?
No, that's incorrect. You can export from a READ COMMITTED transaction; indeed, you'd more or less have to, if you want the control transaction to be able to see what the slaves do. > A "SELECT > count(pg_export_snapshot()) FROM generate_series(1,10000000);" would > quickly bork the pg_snapshots directory which any user can run. Shrug ... you can create a much more severe DOS problem by making zillions of tables, if the filesystem doesn't handle lots-o-files well. regards, tom lane -- Sent via pgsql-hackers mailing list (email@example.com) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers