Обсуждение: BUG #5343: Documentation error for pg_dump

The following bug has been logged online:

Bug reference:      5343
Logged by:          Rob Dean
Email address:      rob.dean@pressassociation.com
PostgreSQL version: 8.3
Operating system:   linux
Description:        Documentation error for pg_dump
Details:

The last sentence of the penultimate paragraph in the Description for
pg_dump in the Documentation states :-

"The tar format (-Ft) is not compressed and it is not possible to reorder
data when loading, but it is otherwise quite flexible; moreover, it can be
manipulated with standard Unix tools such as tar."

and the description of the tar format option states :-

"t
tar
Output a tar archive suitable for input into pg_restore. Using this archive
format allows reordering and/or exclusion of database objects at the time
the database is restored. It is also possible to limit which data is
reloaded at restore time. "

The information on reordering at restore time is surely completely
contradictory between the two. The 8.4 documentation is the same.

"Rob Dean" <rob.dean@pressassociation.com> writes:
> The information on reordering at restore time is surely completely
> contradictory between the two. The 8.4 documentation is the same.

I'm sure that discrepancy goes way back :-(.

Some experimentation indicates that you can reorder some things but not
others --- in particular you can't pull two TABLE DATA sections from a
tar archive out-of-order.  So it might be that someone thought the
restriction had been fixed based on limited testing, and changed one
of the items but missed the other.

I'll see about improving it.

            regards, tom lane

"Rob Dean" <rob.dean@pressassociation.com> writes:
> The information on reordering at restore time is surely completely
> contradictory between the two. The 8.4 documentation is the same.

Actually, on looking closer, I think the original author meant to draw a
distinction between "database objects" and table data items.  It was
certainly confusing though, since it was not stated explicitly that the
former didn't include the latter, and that's not what someone would
expect if they weren't deeply immersed in the guts of pg_dump.  I've
rephrased it.

            regards, tom lane