Re: Automatic free space map filling - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Automatic free space map filling
Date
Msg-id 4714.1141326958@sss.pgh.pa.us
Whole thread Raw
In response to Re: Automatic free space map filling  ("Zeugswetter Andreas DCP SD" <ZeugswetterA@spardat.at>)
List pgsql-hackers
"Zeugswetter Andreas DCP SD" <ZeugswetterA@spardat.at> writes:
> Why do we not truncate the line pointer array ?
> Is it, that vacuum (not the "full" version) does not move
> rows to other pages or slots ? Of course vacuum full could do it,
> but I see your point. 

We can't reassign tuple TIDs safely except in vacuum full.  It's
possible that a plain vacuum could safely truncate off unused line
pointers at the end of the array, but in the absence of a forcing
function to make those pointers become unused, I'm not sure it'd help
much.
        regards, tom lane


pgsql-hackers by date:

Previous
From: Tom Lane
Date:
Subject: Re: [SQL] Interval subtracting
Next
From: Bruce Momjian
Date:
Subject: Re: [DOCS] Online backup vs Continuous backup