You know what I think Postgres needs? Its an official way to declare a
tablespace in a special way that marks the whole tablespace as being
temporary/volatile, so that whenever the server starts/recovers, it assumes this
tablespace doesn't exist or may not exist and can reinitialize it without
trouble. There would also be restrictions then, that certain things may not be
declared in such a tablespace, such as anything but temporary tables, or maybe
some other things. There is such a reasonable use case for this. A feature for
9.4 perhaps? -- Darren Duncan
