Re: Lost my tablespace

On 05/30/2017 01:36 PM, tel medola wrote:
> EXACT !!!!!
>
> When I did the truncate, it erased all the files that referenced the
> table and created a new one (empty). That's why when I returned the
> physical files to the drives, it does not find the old reference and it
> is empty.
>
> I'll search how to redo the link for the correct filenode.
> Thanks very much for your help!!!
>

The thing to remember is:

https://www.postgresql.org/docs/9.3/static/storage-file-layout.html

"When a table or index exceeds 1 GB, it is divided into gigabyte-sized
segments. The first segment's file name is the same as the filenode;
subsequent segments are named filenode.1, filenode.2, etc. This
arrangement avoids problems on platforms that have file size
limitations. (Actually, 1 GB is just the default segment size. The
segment size can be adjusted using the configuration option
--with-segsize when building PostgreSQL.) In principle, free space map
and visibility map forks could require multiple segments as well, though
this is unlikely to happen in practice."

and:

"A table that has columns with potentially large entries will have an
associated TOAST table, which is used for out-of-line storage of field
values that are too large to keep in the table rows proper.
pg_class.reltoastrelid links from a table to its TOAST table, if any.
See Section 58.2 for more information."

--
Adrian Klaver
adrian(dot)klaver(at)aklaver(dot)com