Re: RFC: Restructuring pg_aggregate - Mailing list pgsql-hackers

From Christopher Kings-Lynne
Subject Re: RFC: Restructuring pg_aggregate
Date
Msg-id GNELIHDDFBOCMGBFGEFOOEBGCCAA.chriskl@familyhealth.com.au
Whole thread Raw
In response to Re: RFC: Restructuring pg_aggregate  (Bruce Momjian <pgman@candle.pha.pa.us>)
Responses Re: RFC: Restructuring pg_aggregate  (Bruce Momjian <pgman@candle.pha.pa.us>)
List pgsql-hackers
> Actually, what we need to do to reclaim space is to enable table
> recreation without the column, now that we have relfilenode for file
> renaming.  It isn't hard to do, but no one has focused on it.  I want to
> focus on it, but have not had the time, obviously, and would be very
> excited to assist someone else.

I'm happy to help - depends if it's within my skill level or not tho.  Most
of the time the problem I have is finding where to make the changes, not
actually making the changes themselves.  So, count me in.

> Hiroshi's fine idea of marking certain columns as unused would not have
> reclaimed the missing space, just as my idea of physical/logical column
> distinction would not reclaim the space either.  Again, my
> physical/logical idea is more for fixing other problems and
> optimization, not DROP COLUMN.

Question: Is it _possible_ to reclaim the space during a VACUUM FULL?  I do
not know enough about the file format to know this.  What happens if the
VACUUM is stopped halfway thru reclaiming a column in a table?

Bruce: WRT modifying libpq to do the translation - won't this cause probs
for JDBC and ODBC people?

Chris



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