NetNews Usenet Archive 1993 #1/NN_1993_1.iso/spool/comp/database/sybase/617

Internet Message Format | 1993-01-06 | 1.7 KB

Path: sparky!uunet!munnari.oz.au!bruce.cs.monash.edu.au!merlin!resmel.bhp.com.au!n6batws1.itwol.bhp.com.au!phil
Newsgroups: comp.databases.sybase
Subject: Sybase Data Page Allocation
Message-ID: <[e-mail]>
From: [e-mail] (Phil McMillan)
Date: 7 Jan 93 10:36:33 +1000
Distribution: world
Organization: BHP Steel - Slab and Plate Products Division - Port Kembla AUSTRALIA
Nntp-Posting-Host: n6batws1.itwol.bhp.com.au
Lines: 29

I have a question regarding the allocation of the 2kbyte data pages when they
become "reserved" by tables.

Assume I have a table that typically contains, say, 1000 rows.  If I then for some
reason add an extra 30,000 rows I obviously will take more than a few data pages
from the pool of storage (and at least 8 of them.)

From what I understand, these data pages (for indexes and rows) are now owned,
or reserved, by the table.

If I delete these 30,000 rows, will/should these data pages become returned to
the pool?

The reason I ask this is because some of my tables have far more reserved space
than what is currently needed for the data and indexes, far more than
the 16kbyte page allocation increment. We use SYBASE in a production environment
and we need to be able to predict how SYBASE will behave in exceptional
circumstances, hence my interest in how the page allocation mechanism works.

--
   /\/\     :  Phil McMillan - Electrical / Software Engineer
  / / /\    :  Engineering Technology Department
 / / /  \   :  BHP Steel - Slab and Plate Products Division
/ / / /\ \  :  P.O. Box 1854 Wollongong NSW 2500 AUSTRALIA
\ \/ / / /  :  Phone    [phone]
 \  / / /   :  Fax      [phone]
  \/\/\/    :  E-mail   [e-mail]