Horton

Re: AW: update on TOAST status'

Bruce Momjian <pgman@candle.pha.pa.us>

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From: Bruce Momjian <pgman@candle.pha.pa.us>
To: Zeugswetter Andreas SB <ZeugswetterA@wien.spardat.at>
Cc: "'Jan Wieck'" <JanWieck@Yahoo.com>, Tom Lane <tgl@sss.pgh.pa.us>, PostgreSQL HACKERS <pgsql-hackers@postgresql.org>
Date: 2000-07-11T14:49:20Z
Lists: pgsql-hackers 
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> 
> >     It appears that brtee indices (at least) can keep  references
> >     to  old  toast  values  that  survive  a  VACUUM! Seems these
> >     references live in nodes actually not  referring  to  a  heap
> >     tuple   any   more,   but   used  during  tree  traversal  in
> >     comparisions.  As if an index tuple delete from a  btree  not
> >     necessarily  causes  the  index  value  to disappear from the
> >     btree completely.  It'll never be returned by an index  scan,
> >     but the value is still there somewhere.
> 
> Would it be possible to actually delete those entries during vacuum ?
> I guess that would be an overall win, no ?

Seems that is the only good solution, or somehow link vacuum of TOAST
tables to index so these TOAST values are not removed.

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