Re: COPY and file_fdw with fixed column widths

On Tue, Apr 28, 2015 at 12:46:22PM -0700, Tom Lane wrote:
> Bruce Momjian <bruce@momjian.us> writes:
> > I know COPY doesn't support importing files with fixed column widths,
> > i.e. we can't say field1 is the first 30 characters, and field2 is the
> > rest of the line.  We need a unique delimiter at column 31.  (Commercial
> > Ingres does support this ability.)
> 
> > I know we tell most people to use sed, Perl, or an ETL tool to convert
> > files into a format COPY understands, and I think that is a reasonable
> > answer.  However, the file_fdw also reads our COPY format, and in that
> > case, the data file might be updated regularly and running an ETL
> > process on it every time it is read is inconvenient.
> 
> COPY is, and has always been intended to be, as fast as possible; loading
> format transformation abilities onto it seems like a fundamental mistake.
> Therefore, if you wish file_fdw were more flexible, I think the answer is
> to create a variant of file_fdw that doesn't use COPY but some other
> mechanism.

Yes, I think this is a missing feature.  While we can tell people to do
ETL for loading, we are really not doing that for file_fdw.

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com
 + Everyone has their own god. +