original file won't open

[Debbie S.]

I created a database and stored it in a folder on my c drive. I then used the
database utility function in access to split the database, and then I created
a backup. At some point I moved all three of these files--the original (we'll
call it database y.mdb), the backup (database y_datebackupfilecreated.mdb),
and the back end (databasey_be.mdb)--into a new folder, still on my c drive.
Now for some reason when I open the file called database y.mdb, I get a
message that says the path is not valid. The path quoted in the message is
the OLD folder name; and, if I click okay on the message, I can see in the
database window that the tables in database y.mdb are the split ones that
have the arrows by them. Why won't the file open, and why does the original
file I created store the split tables? I thought the whole point of splitting
was to create a file that is based on the original that will not allow users
to mess with the tables. Why does the original file have the split tables?
I'm confused. Can someone please help me clear this up.

Many Thanks,
Debbie

 

[Ken Sheridan]

Debbie:

You'll need to refresh the links so that they point to the new location of
the back end file. Do this with the built in Linked Table Manager (Tools |
Database Utilities | Linked Table Manager on the main database menu bar –
though it might differ depending on which version of access you are using).
Each linked table has a Connect property which is a string identifying the
location of the actual table; its this property which is updated when you use
the Linked Table Manager.

Slitting a database is rather more than preventing meddling by users.
Unless you've implemented user and group security there is nothing to stop
them simply opening the back end directly and amending the table definitions.
The main purpose of splitting a database is so that users can share access
to the same back end over a network, while having a copy of the front end on
each local machine, the most efficient set-up for a multi-user application.
Even with a standalone database on a single machine splitting it has
advantages, though. If the front end is corrupted the data is not affected
and its simply a case of installing a new front end from the original
development copy. Also the data can be backed up regularly (you do that,
don't you!) without having to back up all the unchanging elements of the
front end.

The reason "why does the original file I created store the split tables?" is
simply that when you split it Access moved the original tables to the back
end and replaced them in the front end with links to the new locations.
That's how it works.

Ken Sheridan
Stafford, England

 

[Debbie S.]

Ken,
Thank you, I was able to refresh the links. However, I am still confused
about front end/back end. If I want to make changes to the database that will
also apply to the front end copies on other users' local machines, where do I
make those changes? As far as I can tell the back end file contains only the
tables. If I want to make changes to a form or query that will also change in
the front end copies on three different machines, how do I do this? Also, I
was thinking that I would put a front end copy of the database in a shared
drive folder on our network, which all users can access from their machines.
What are the pros and cons of that type of set up as opposed to the one you
are suggesting?

Lastly, when I opened the original database with the split tables, I was
still able to change data in the tables. Is this supposed to happen, or does
splitting only restrict users from changing table structures--properties,
fields, etc.? Should I make the tables in the front end read only?

Thank you again, your help is much appreciated.

Debbie

 

[Ken Sheridan]

Debbie:

To change the design of the front end you'd do so in your own 'master' copy
of it as the 'developer'. Then you'd replace the copies on each users local
machine with a copy of your amended file. This can be automated via the
network. You'll find one example of a utility or doing this at the following
link, and I'm sure that if you Google around a bit you'll find others. I
have developed one myself, but it is application specific, whereas that at
the following link is generic:


http://www.access-programmers.co.uk/forums/attachment.php?attachmentid=14316&d=1153822461


It is possible to have a single front end in a shared folder, but it is not
recommended.

Splitting the database will mean that users can't change table definitions
via the links in the front end, but they can easily navigate to the back end
file via My Computer or Windows Explorer and open it directly, in which case
they could do anything they want with it. As far as editing the data is
concerned users can do so via the links just as if they had opened the tables
directly. Usually this is what's wanted of course as users will be updating
data on a day to day basis in most applications.

If you want to prevent users amending either the table definitions or the
data then you'd really have to implement user and group security. You'll
find a detailed explanation of this at the following link. Before starting
you should back up your files and read the article very carefully until you
are sure you fully understand what's involved. Its not difficult to
implement if you follow the instructions in the article step by step, but its
not unknown for people to mess things up following only a brief perusal of
the article:


http://support.microsoft.com/default.aspx?scid=/support/access/content/secfaq.asp


Ken Sheridan
Stafford, England