Can user level security enable someone to access a form, but not access a table? I have a form that is connected to a table using a"SELECT" command. It does not "UPDATE" or "DELETE". I'd like for the user to access my form, but I don't want them to be able to view the details in the underlying table. I've tried all sorts of combinations in the user level security wizard, but for some reason, my form comes up blank, unless I give complete access to the user to do anything. Any ideas? By the way, I'm on Access 2003.
You could make an MDE and give it to your users. If you do this, the users won't be able to see anything but the user interface you have provided.
If your tables are in the same Access database as the forms and queries, you first need to "split the database" into a frontend and backend. See:
http://databases.about.com/od/tutorials/ss/splitaccessdb.htm
for information on how to do this. The frontend contains everything but the tables. The backend contains the tables. The frontend is linked to the backend tables using "linked table" objects in the frontend.
Once the database is split, open the frontend in Access, and create an MDE by selecting Tools/Database Utilities/Make MDE File from the menu bar. The MDE is what you provide to the users. They open it the same way they would any other database, except that they can't design any of the objects.
Make sure that you have an AUTOEXEC macro defined in the frontend, so that when the MDE is opened by the user, it has an entry point. The user cannot see any of the objects in the MDE, so if you don't have an AUTOEXEC macro to open the first form, nothing will happen when they try to open the MDE.
If you need the ability to manage the linked tables in the MDE by allowing the user to connect to the backend database with a File/Open dialog, see the following article:
http://www.mvps.org/access/tables/tbl0009.htm
OF course, none of this precludes your users from opening the backend database. If you need stronger security, you can upsize the backend database to SQL Server Express. More info here:
http://office.microsoft.com/en-us/access/HA102755371033.aspx
What you're looking for is a RWOP query. That means "run with owner permission."
To make it work, assuming you've already run the security wizard on your front-end and back-end databases and have removed permissions for the users to even read the tables, you then create a saved query as the recordsource of your form. In the properties of the query, it is set by default to RUN PERMISSIONS as "user's." Change that to "owner's" and save the query. The query will run with whatever permissions on the base table the owner of the query has. If you are running as an administrator with full permissions, you'll want to set the permissions of the saved query to read-only (or create the query under a user logon that has read-only access to the tables -- it's much easier to do the former).
Some caveats:
user-level security is tricky. If you miss even one step outlined in the ULS security white paper, your app won't be secured. The way to test this is to open Access with a default workgroup file and then see if you can access the objects in your database logged on as the default admin user. If you can, then you made a mistake somewhere along the line.
user-level security is crackable by anyone who wants to. This doesn't mean it's not useful, it just means that it's not bullet-proof. I don't worry about that so much, as I consider security as much a people problem as a technical problem -- you have to give employees sufficient privileges to do their work, and you have trust them that they won't abuse the privileges you've given them.
if you're running Access 2007 and using the ACCDB format, RWOP queries are not available to you, as Jet user-level security is not supported for the ACCDB format. If you're using MDB format, though, it will work just fine in A2007.
Related
I am just a beginner, as such, humbly request you to be as basic as possible.
below are the steps that I had taken while creating a split access database:
Originally created an access database in access 2013, which had a login form as default form on load, and it was mandatory to log in.
Split the database into back-end and front-end.
stored the back end database over the network in one of the computers (all systems are linked via LAN/wi-fi) and distributed the front end to different users.
This setup had worked fine so far. Users were able to operate the database perfectly fine. However, it was required that the database be imported back again (merge front-end and back-end). Below are the steps that I took.
Logged in as a superuser (there is a feature where I can bypass the login form by using shift+enter key, which then asks for superuser credentials. Once logged in, simply close the database and again open using shift+enter) and gained access to database design.
deleted the linked table, and imported the back-end database.
Now, when I connect my system to the network, and try opening the database, everything works fine. But if I disconnect from the network and try to open the database, IT JUST WON'T OPEN. Only the access software gets opened, and not the database.
What I fail to understand is why is my database still dependent on network when there clearly is no need for that?
Please help me understand where I am wrong, and also, how can I open the database without being connected to the said network.
(As per this meta post, I should repost my comment as an answer).
There were still linked hidden tables present. See here how to unhide them.
I'm creating an Access 2010 database and would like some clarification when it comes to concurrency and security. What I would like is upon starting the app only a menu form to be displayed with several buttons including a login button. Most buttons would be disabled until after the user logs in at which point based on their permission group; Viewer(Deafault), Worker, Editor, Admin.
Also, Admin should be the only one to be able to see the access database while the others are restricted to seeing the forms only.
I was just testing the default concurrency implementation but saving my database to a shared network and having myself and a co-worker try to access it. Found out if one accessed the database it locked it from others, and if we both tried at the same time it became read-only.
So I'm just looking for tips on how to start this.
For an Access database all users must have as a minimum read, write and modify permissions on the folder in which the database resides. This is because MS Access creates a lock file and if the second user does not have permissions to modify the lock file, the cannot get access to the database. Delete permissions may also be useful, to remove the lockfile when they are the last person out.
Is there a way to secure tables in ms access db from unauthorized access? I would like my users to use the forms in the db but i don't want them to see the contents of the tables. I know i can hide a table but anyone who knows just a bit about access can show the hidden tables anyway. I cna also change a name to UsysTableName but again - enabling system tables shows them all. Is there a safer way? Securing by password maybe?
Also in access there are users and groups, and the possibility of granting rights.
You can access this functionality via tools/security/user and group permissions.
You need to create a workgroup information file in order to use this :
see : http://www.databasedev.co.uk/access_security.html
NOTE : Indeed Ms Access is in most cases a poor choice of db. But if you have to keep on using it for one reason or another, learning its security model is imperative in real world apps.
For Access 2003 Understanding the role of workgroup information files in Access security at http://support.microsoft.com/kb/305542/.
For Access 2007 How to use the Workgroup Administrator utility in Access 2007 at http://support.microsoft.com/kb/918583.
In your case, I suggest moving the tables you want to secure into a different database then link to the User-Interface (front end) database. This allows you more control over security. Using a password only keeps non-users out of the database. Logged in users can still see the tables.
One solution is to have your forms on one side (client side) and your tables on the other side (server side). Each user has only a copy of the forms, and the tables are somewhere else on the network.
Another solution is to install the runtime version of access (free to use) on user's computer. In this case the database window does not appear.
Whatever is you choice, you'll have to fully manage access to commandbars, creating you own ones (and forbidding the display of access commandbars).
If you go for the first solution, you'll be on your way to a real client/server structure, and you'll be able sooner or later to switch to SQL Server for your tables (your forms can then stay in an Access client application).
With some limits, it is possible to completely delete the links to the back-end tables in the front-end/app:
During app open, just use ChDir "\\someShare\someFolder" in VBA
As the source of your forms & reports, use SQL SELECT instead of saved queries/tables, using the syntax: SELECT field1, field2 FROM [BackendName_be.mdb].myTable. Note that the path is NOT specified!
This way the forms/reports will work perfectly, without any table (not even hidden) in the app.
If you put the BE in a hidden folder/share and you deliver an MDE, users will have a very hard time finding where the data is.
This technique has the added benefit to allow instant switching of the back-end (like between test/prod).
Access does a very poor job of securing data in tables. Your users NEED access to the tables in order to work with the data, but you don't want them possibly seeing EVERYTHING. You could encrypt the data in your tables yourself on the fly. I talk about this in my Access Data Encryption seminar.
What is the simplest way to allow one user write access and everyone else read-only access to a MS Access database on a local network?
I trust my users, but unfortunately Access saves changes to data as soon as the row of a table is deselected. Accidental keystrokes are saved without the user asking for the changes to be saved.
Some thoughts on controlling user rights to a Jet data store:
if you really want to lock things down, you'll never manage it with Jet, as it's inherently vulnerable because the user has to have WRITE access to the MDB file.
if you are content with controlling rights to the data in your front-end application, you could provide different front ends (one for WRITE users and one for READ-ONLY).
if you're not using ACCDB format, you can use Jet user-level security. It's a surprisingly complicated technology if you really want to lock down access to the data -- you have to follow all the instructions in the Jet Security White Paper to the letter, or your data will be open to anyone with the standard Jet workgroup file. And even once you're done, it is crackable (though not without spending $$$ to buy cracking software). BTW, database passwords before Access 2007 were completely useless and easily cracked. Access 2007 enhances the security by raising the level of data encryption, but a database password causes lots of issues and doesn't allow you to have more than one level of access (unless you provide two different front ends with different passwords -- cf. #2).
if you just want to use Jet ULS to control access in your front end, you can add your users to groups and then check the group membership in your front-end UI objects (i.e., forms), and give WRITE permission to the users who are in the user group that provides that level of access. The easiest way to do this, assuming you have more READ-ONLY users than those with WRITE permission is to have the READ-ONLY users log on as the default admin user (i.e., you do nothing for their setup), and have the WRITE users log on as a user in the group with WRITE permission. In other words, if they aren't logged on as user "admin", they have full WRITE access.
another alternative is to use NTFS security groups. API code for that is found on the Access Web, but it does require a Windows administrator to implement for you. Again, you would be limiting access in your front end application, rather than actually restricting user rights in the back-end MDB.
Only Jet ULS actually allows you to prevent a READ-ONLY user (who hasn't cracked your workgroup file) from editing your data. All users have to have network access to your back-end MDB, but you can make it hard for them to get to the data even without jumping through the hoops in implementing Jet ULS. Here are some steps to do that (and yes, all of these are a form of "security by obscurity" and will only slow down a READ-ONLY user determined to hack your back end):
Right click each table in your back end and turn on the HIDDEN attribute. This can also be done in code (see SetHiddenAttribute in Help). Naturally, if the end user sets their Access options to display hidden tables, this won't do anything. But most end users don't know about that, and if your users are running your app in the runtime, they won't have the option.
Change the back-end database's Startup Properties to not display the database window and to not use special keys. You can find code for setting the startup properties in the Help topic for "AllowBypassKey".
In your back-end, create a macro named AutoExec with one command, Quit. With special keys disabled, there is no way to prevent the execution of this macro, and as soon as the user attempts to open the back end (even if they hold down the SHIFT key, i.e., the standard keystroke for bypassing all startup routines), the database (and the instance of Access) will close.
Now, all of these things can be undone by someone who knows what they are doing. If you gave me a back end with these things implemented, I'd be in it in about 5 minutes, simply by running code in another Access database to change all these startup properties to give me access.
But your end users likely don't have that level of expertise. Any such user who does probably ought to be a WRITE user, no? :)
Yes, of course -- all of these things are easily hackable by anyone who knows how. But it's also easy to break into your house in seconds for the person with the right tools. That doesn't mean you don't lock the doors, even though it's not bulletproof protection from burglary.
Another consideration is that if you provide your users only the Access runtime instead of full Access, they won't be able to undo any of these settings in your back-end MDB.
Last of all:
Security is not solely a technical issue -- most of it is, in fact, a people problem. In order for people to do their work, you have to trust them to a certain extent in giving them access to your data. There is no technical solution to the problem of the untrustworthy system administrator, for instance, and the only way to fully protect your data is to not give them any access to it at all.
The easiest way would be to use share permissions. Grant write access to a group and put the users who must write to the database in that group. Put everyone else in a read group. This assumes you have a Windows domain, of course.
Here is a site that has some information on securing Access databases. It deals with Access 2000, there may be more options for newer versions.
This is the cheeky answer, but if you need better security, seriously consider upgrading to a more robust RDBMS.
I think it is possible using an ODBC connection to use Access as an interface to almost any database. For example, I have successfully configured a SQL Server 2008 Express Edition database with 2 users, one read/write and one read-only. I have been able to connect to the database from Access by opening an ODBC data source. So a user can have the Office-based report-generating and mail-merging functionality they are familiar with. But with any database server you wish.
This conversation may be a little old, but for some reasons I got the same problem recently. It will not suit to everyone, cause it relies not on M$ SQL Server but on MySQL. Use the MySQL ODBC connector (available here: http://dev.mysql.com/downloads/connector/odbc/), and store your tables on a MySQL server. The Access user's rights on tables will inherit from the MySQL user's rights. Pretty easy to customize...
Fact is, there is NO functional security for an access database.
The link below sells software that will 'recover' your access database Even if it has a a password.
It is a good thing they exist. Their program saved one of my customer's butts once when their previous programmer died and no one else had the password. Thanks to this program we could not get in and no data was lost.
http://www.stellarinfo.com/access-recovery.htm
And before you even think it, No, I do not work for them.
I maintain an ms-access application splitted to frontend and backend files.
The frontend file is in the users conputers.
The backend file is in a shared folder in the server.
What is the lowest permissions required?
can I give some of the users only read-only permissions in that folder? (or hide it from them in some other way) but still enable them to view the data?
How should I give the best security to the data file and to the folder containing it?
Unfortunately, the lock file (ldb) must be created, updated and deleted. If a user with insufficient permissions opens the database, it will be locked for all other users, therefore all your users need Read/Write/Delete permissions on the back-end.
EDIT #1
The lock file must be created every time the database is opened, this includes via linked tables, and deleted when the database is closed. If a lock file exits and the database is closed, it indicates a problem has occurred. You will also run into problems with compact and repair if it is run with insufficient permissions.
Edit #2
Security for Access is quite a large subject and depends to a great extent on your environment and requirements, for the back-end, it ranges from a database password, which is tissue thin, but quite suitable for most offices, to Access security, which can be complicated and has been dropped in 2007. Here is a link http://support.microsoft.com/kb/207793 for a download for the Microsoft Access Security FAQ for versions < 2007.
Information on security for 2007 can be found here http://www.microsoft.com/technet/security/guidance/clientsecurity/2007office/default.mspx.
Many have suggested that you must give FULL permissions to users, but this is not true. You need only give them MODIFY permissions -- you can deny them DELETE permission, which is a good idea, as it prohibits the users from "accidentally" deleting your data file.
It is true that for a user with DELETE permissions, the LDB file will be deleted on exit when that user is the last user exiting the database. But it is not required that the LDB file be deleted -- indeed, in Access 2 and before, the LDB files were not deleted on exit, but just left there hanging around. This generally has no downside, but occasionally the LDB file gets corrupted and causes problems and really does need to be deleted and recreated afresh.
What I do is have two classes of database users (as defined in custom NT security groups specific to my Access application(s)) -- DBAdmins and everyone else. The DBAdmins have FULL permissions, everybody else only CHANGE. The result is that any time a DBAdmin exits as the final user, the LDB is deleted. This setup works really well, and I've been using it for well over a decade.
Using a hidden share for your back end is really only "security by obscurity," and not really worth the effort. Sophisticated users can figure it out through any number of methods (depending on how you've locked down your front end):
view the MSysObjects table and find
the CONNECT string for the tables,
which will identify the hidden
share.
examine the results of
CurrentDB.TableDefs("name of linked
table").Connect in the immediate window in
the VBE
Now, if you've properly secured your app using Jet user-level security (and it's very easy to think you've secured your database and find out that there are holes, simply because it's really easy to forget some of the crucial steps in the process), they won't be able to do this, but even if you have, Jet ULS security is crackable (it's pretty easy to Google it and find cracking software), so is not really something you should depend on 100%.
Yes - it resolves down to file access permissions as well as read/write. You can't execute any type of data update stuff (you'll get "operation requires an updateable query") unless the user supplies credentials that allow them to write, or you allow write on the file.
Running a query requires only read access.