Re: pctfree and pctused

Sure pctfree is the amount of space Oracle will leave in a block for future updates to the rows which reside in the block. Pctused is used by oracle to determine when to place a block on the freelist, or take it off. For example if your tblsp has say pctfree 10 and pctused 40, Oracle will reserve 10% of each block containing rows in that tblsp for future updates to those rows, and since your pctused is 40% Oracle will place the block on a freelist (meaning more rows can be inserted into it) once it falls below 40% usage. These parameters must be set properly for your database to operate at its peak
D Parent

José Antonio Morcillo Valenciano <jamv_at_gtt.es> wrote in message news:38BF6A06.C9C3D73_at_gtt.es...
> Sorry for my newbie question but could anyone explain easly what is
 pctfree and
> pctused!
>
> thank you!
>
> dgpare wrote:
>
> > The 20% Pctfree would be used for future inserts if you left it that
 way,
> > and in Oracle pctfree and pctused can not add up to 100. Try pctfree 0
 and
> > pctused 99 if you are sure there will be no updates to the table.
 However if
> > you do this and find you are updating the table you will run into row
> > migration which is a new ball of wax.
> > <ewong_at_engineer.com> wrote in message
 news:89jtf8$5cm$1_at_nnrp1.deja.com...
> > > Hello,
> > >
> > > I have a huge table that only being inserted but never updated.
> > > Currently pctfree is 20 and pctused is 40. I would like to save some
> > > space by changing them to pctfree 0 pctused 100. My questions are:
> > >
> > > 1. Is the 20% free space going to be reuse for future insert?
> > >
> > > 2. How come I can't set pctused to 100? It gave me an
> > > ORA02211.
> > >
> > > Thanks,
> > >
> > > ewong
> > >
> > >
> > > Sent via Deja.com http://www.deja.com/
> > > Before you buy.
>
Received on Fri Mar 03 2000 - 00:00:00 CST