Re: Tablespaces

Tom Lane wrote:
> Gavin Sherry <swm@linuxworld.com.au> writes:
> > A table space is a directory structure. The directory structure is as
> > follows:
> > [swm@dev /path/to/tblspc]$ ls
> > OID1/    OID2/
> > OID1 and OID2 are the OIDs of databases which have created a table space
> > against this file system location. In this respect, a table space
> > resembles $PGDATA/base. I thought it useful to keep this kind of
> > namespace mechanism in place ...
> 
> Actually, this is *necessary* AFAICT.  The case that forces it is DROP
> DATABASE.  Since you have to execute that from another database, there's
> no reasonable way to look into the target database's catalogs.  That
> means that the OID of the database has to be sufficient information to
> get rid of all its files.  You can do this fairly easily if in each
> tablespace (whose locations you know from the shared pg_tablespace
> table) you can look for a subdirectory matching the target database's
> OID.  If we tried to put the database's files just "loose" in each
> tablespace directory then we'd be in trouble.
> 

Gavin, let us know if you want us to create the global pg_tablespace for
you.  Some of us have done a lot of system catalog work.

--  Bruce Momjian                        |  http://candle.pha.pa.us pgman@candle.pha.pa.us               |  (610)
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