Re: ** chained rows fixing

  • From: Mladen Gogala <gogala@xxxxxxxxxxxxx>
  • To: mwf@xxxxxxxx
  • Date: Sat, 24 Sep 2005 18:15:47 +0000

On 09/24/2005 10:48:22 AM, Mark W. Farnham wrote:
> Mladen:
> Amazing! I had no idea that 85 percent free would magically shrink rows
> larger than the usable space in a single block!

Nothing would shrink those rows. If you have 250k long rows, you are beyond 
help and 
your application model is probably dead wrong. Tom Kyte has an example of such 
case in
his book, when the designers have created each string column as VARCHAR2(4000). 
Once you 
start entering yellow pages in a single row, you will get chained rows.
Incorrectly set PCTFREE in a frequently updated table is a rectifiable thing 
which will be 
rectified by rebuilding the table with the proper PCTFREE. It will also rid you 
of the
migrated rows.

Mladen Gogala


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