[thelist] Online Database Dumb Question

Ken Schaefer Ken at adOpenStatic.com
Wed Mar 2 18:02:07 CST 2005


The situation you are in is a little bit unusual IMHO. I would expect that
you probably wouldn't be able to delete the .mdb file for about the first
second or so after you've had some other process access it, but if you've
waited more than a few seconds, there shouldn't be any other process
accessing it.

Now, there's a difference between "unlocking" a Jet .mdb file, and ensuring
that no process has a file system lock. 

When you access a Jet database file, a corresponding .ldb lock file is
created, which contains information about users and what locks they have on
what within the database. It's important to note that these are database
locks (i.e. locks on objects within the database, not on the actual files
themselves, i.e. not file system locks). When the last user releases the last
lock, that user is supposed to delete the .ldb lockfile. If NTFS permissions
are not configured correctly, this doesn't happen, and you can end up with
some issues accessing the database.

However, these are database locks, and have nothing to do with the file
system per se. Furthermore, failing to close your DB connections would result
in open DB locks, but wouldn't result in file system locks (and restarting
your website certainly wouldn't close any open DB locks, but it might stop
the web server's process from accessing the file).

So, given that they had to restart your site to get the file "unlocked"
(whatever that means), I suspect that you have some kind of file system lock
on the DB. I would ask your host to run Handle.exe from www.sysinternals.com
to find out what process has what type of file system lock on the .mdb file
in question.

Cheers
Ken

: -----Original Message-----
: From: thelist-bounces at lists.evolt.org [mailto:thelist-
: bounces at lists.evolt.org] On Behalf Of Administrative HQ
: Sent: Thursday, 3 March 2005 8:46 AM
: To: thelist at lists.evolt.org
: Subject: [thelist] Online Database Dumb Question
: 
: Hello.
: 
: I have an online database to which entires are made by
: ASP forms. Manual editing is possible.
: 
: I didn't create the system and don't know anything
: about ASP or much about data bases.
: 
: I used Access to add some columns to the data base,
: with an eye to manually adding information, using the
: "Edit" function. These columns are unrelated to
: anything called by the VBscript in the forms...they're
: just sitting in the data base.
: 
: I used the regular form to create a data base entry
: (new user) and it worked fine...making the right
: entries in the dbase but having no effect, of course,
: on the new fields.
: 
: I did not make any manually entries as I was merely
: trying to see if the new columns came up right and if
: the forms still worked.
: 
: But then, I was unable to rename, delete or replace
: the dbase. Two ftp clients returned error notices
: saying that the file was in use by another process
: (although Access, IE, etc,. had been closed. The
: support folks on my host had to reboot the site to
: "unlock" the mdb file, which had "not closed
: properly".
: 
: Can I not do what I'm trying to do, or is this just a
: quirk?
: 
: Any help or pointers would be greatly appreciated.


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