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Like FMS Products? The Toolbox About The Editor Garry
Robinson writes for a number of popular computer magazines, is now a
book author and has worked on 100+ Access databases. He is based in
Sydney, Australia
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The
The LDB File
Whenever you open an Access database, Access will open a file with the same name as the database and an extension of .LDB. This file type is known as a locking information file. For example, if you open Northwind.mdb in the samples directory of your Access/Office installation, a file called Northwind.ldb will be generated. This new file keeps track of users and the locking status of every object that requires some form of locking in the database. When all users have exited the database by closing it in an orderly manner, Access will close the .LDB file and delete it.
The internals of the .LDB file are
important for database sharing. The file stores the computer name and
workgroup file security names of those users who are currently logged on to
the database (with the occasional exception). It also stores the objects that
that user has open or locked in a special and flexible part of the workgroup
file.
NOTE Access needs to delete the .LDB file when it closes so that databases
work properly and to allow for performance improvements when determining which
other users have locks. Therefore, everyone who uses the folder in which the
database is stored will need write and delete permissions for files in that
folder. You will find out more about Windows folder permissions in Chapter 12.
To find out more about the .LDB format,
read the white paper
Understanding Microsoft Jet Locking (LDB Files) by Kevin
Collins. This paper is included in the LDBView download files, or you can find
a link to it in the “Further Reading” section with other .LDB pages at the end
of this chapter.
Click on the following button
This topic and more are discussed at
length in Chapter 6 of Garry's Book on Access
Protection and Security
Read More
You should also read more
on the ldb file in the
help provided with the Access Workbench
Microsoft
Access Passwords, Workgroups and ADO
Take Advantage Of The
Class Module Features Of Your Access Forms
to jump to the next page in the protection samples loop.