[AccessD] notes on mdb bloat

John Bartow john at winhaven.net
Wed Mar 3 11:23:43 CST 2004


Gustav,
It would certainly seem that way.

It appears, at first glance, to be a work-around solution to achieve
row-level locking rather than a permanent, engine level solution.

But it may have been done this way for Jet and backward compatibility
issues.
(?)

John

-----Original Message-----
From: accessd-bounces at databaseadvisors.com
[mailto:accessd-bounces at databaseadvisors.com]On Behalf Of Gustav Brock
Sent: Wednesday, March 03, 2004 11:11 AM
To: Access Developers discussion and problem solving
Subject: Re: [AccessD] notes on mdb bloat


Hi all

Does this - simplified - boil down to, that all row-level locking does
compared to page-level locking is bloating a row to fill a page?

/gustav


> Hi Seth et all

> In Garry Robinson's newsletter I noted this extremely interesting topic:


> SINGLE RECORD LOCKING, BLOAT AND CITRIX BUGS

> Did you know that the record-level locking option (menu
> Tools~Options~Advanced) that is used by Access 2000 onwards has an
> interesting twist. To achieve a single record lock, each record that
> is locked uses up all of an Access page in the mdb file. This page of
> data, most of which will probably be empty for records with only a few
> fields, consumes 4000 bytes. This space is later recovered when the
> database is compacted but if you have a database that seems to expand
> fast, this could be your culprit. For more on this database bloat and
> a possible cure for Access corruptions for Citrix head to this page.

> http://ewbi.blogs.com/develops/2004/01/access_corrupti.html

> and an other blog on the same topic
> http://dbforums.com/arch/213/2002/10/551337

> Gary is here:

> http://www.vb123.com/

> /gustav


>> I hadn't even thought of that.  I tried it just now, and the resulting
>> mdb is 1.5MB.  Still three times as big as the A97 version, but not as
>> big as the base A2K version.

>> The unicode comments make sense, I had forgotten about that, too.

>> Oh well, more interesting info from the developer front...

>> Seth

>> On Wed, 2003-03-12 at 11:45, Gustav Brock wrote:
>>> Hi Seth
>>>
>>> What happens if you "forward port" the A97 version to A2000?
>>>
>>> /gustav

--
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