(2012/03/16 22:51), Shigeru Hanada wrote:
2012/3/16 Etsuro Fujita<fujita.ets...@lab.ntt.co.jp>:

The index creation is supported for a flat file such as CSV and a remote
table on a RDB e.g., Postgres using CREATE INDEX.

IMHO CREATE INDEX for foreign tables should have general design,
not specific to some kind of FDWs.

OK. I'll try to design CREATE INDEX more generally, though I'll at first focus on those two.

I'd like to build the index physical data file for a flat file using the
index access method of regular tables (ie btree, hash, gin, gist, and
spgist) based on the following transformation between the TID and the
file offset to some data in the file:

    block_number  = file_offset_to_some_data / BLCKSZ
    offset_number = file_offset_to_some_data % BLCKSZ

Indeed these information would help searching data stored in local
files.  But, again, it seems too specific to file-based FDWs.  I'd
suggest separating basic general design and implementation by FDWs.
The design you shown here seems indexed-file_fdw to me...

This transformation is for a flat file. I think an FDW author who wants to build the index physical data file for an external data may choose any transformation that defines a one-to-one mapping into the TID space.

Best regards,
Etsuro Fujita

--
Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-hackers

Reply via email to