User Permissions

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Guest

I have created a database with a password form where i put username and
password. That is working very well.
Now i have a question: its possible define permissions to users and
administrator, using this form, and not permissions of the database? If is
possible how can i do that?
 
I have created a database with a password form where i put username and
password. That is working very well.
Now i have a question: its possible define permissions to users and
administrator, using this form, and not permissions of the database? If is
possible how can i do that?
Click to expand...

You'd need to add a table to your db that would store your permissions for each object and user, then query that table
when the user successfully logs in.

Here's a link that may help get you started. It deals with protecting a Form, but the basic concept and table design
might be useful to study:

http://chazelleconsulting.com/Resources/Database/Password-protect_a_form.htm

Scott McDaniel
scott@takemeout_infotrakker.com
www.infotrakker.com
 
I've tried what says this link (
http://chazelleconsulting.com/Resources/Database/Password-protect_a_form.htm)
but does'nt work.
what is wrong??
Click to expand...

I don't really know what you mean by "doesn't work", but the link was intended to give some guidance on doing this, not
really step by step instructions. Sorry about any confusion.
Now i have a question: its possible define permissions to users and
administrator, using this form, and not permissions of the database? If is
possible how can i do that?
Click to expand...

You can certainly store User/Group and Object permissions, but I can't really advise you how to do this, since I don't
know your table structure. However, basically you'd do this:

1) Store Users
2) Store Groups
3) Store Objects
4) Store User-Group memberships (i.e. Which users belong to which groups).
5) Store User/Group - Object permissions (Which Groups can/cannot access whic objects)

Which basically means you'd need 5 - 6 tables to do this. I'd also advise you to ONLY do this with Groups, as trying to
keep track of User permissions can be tough.

So when your login form authenticates a user, you'd (probably) store the UserID in a Global variable, or in a Table
somewhere. Then, as your user attempted to open a Form or Report, you first (a) query the User/Group-Object permissions
table for your specific User/Group and Object and then (b) allow or disallow the action, based on the results from that
table.

I'm not sure what you mean by "not permissions of the database". Can you explain a bit more on that?

Scott McDaniel
scott@takemeout_infotrakker.com
www.infotrakker.com
 
By "not permissions of the database" I mean: How I have 2 Databases and users
and permissions are not the same, I dont want set permissions on access
Tools»Security»User Permissions and workgroup.
I dont know if you understand but im Portuguese and my english isnt good,
sorry.

"Scott McDaniel" escreveu:
 
By "not permissions of the database" I mean: How I have 2 Databases and users
and permissions are not the same, I dont want set permissions on access
Tools»Security»User Permissions and workgroup.
I dont know if you understand but im Portuguese and my english isnt good,
sorry.
Click to expand...

Not a problem, just wanted to make sure that we understood each other.

So you don't want to use ULS for this? In your case, since your not really concerned with data security but more with
navigating in the database, ULS is a great choice (and you can have two different groups of users with ULS). ULS has
builtin properties and methods which do exactly what you're trying to do - it tracks Users, Groups, User-Group
Memberships, and User/Group Object permissions. Once you've setup ULS, you then can use the CurrentUser function to
determine who is logged on, then use several custom function to determine if the CurrentUser has permissions to open a
form, a report, view a query, etc etc ... or you can just let Access throw the default error message when they try to
view an object for which they have no permission.

However if you want to build your own login and navigation scheme, then perhaps this will work:

http://www.databasedev.co.uk/login.html

From here, you could add your Objects and ObjectPermissions tables, and then query those tables whenever a user tries to
open a form ...

Scott McDaniel
scott@takemeout_infotrakker.com
www.infotrakker.com
 
I've used that login form and its working well.
Now i want to know how i can set the users permissions based on taht form
and table.

"Scott McDaniel" escreveu:
 
I've used that login form and its working well.
Now i want to know how i can set the users permissions based on taht form
and table.
Click to expand...

Do you have a table containing your Objects and Object Permissions? You'll have to do this, and without knowing your
database structure it's impossible to advise you how to continue. If you can post the structure of the tables you're
using to store Object names and Object-to-User/Group Permissions, then perhaps we can asist further.

Basically, once the user logs in you would then simply query the tables to determine if the logged-in user has
permission to open a form/report etc. So if you're storing the username in a variable named "CurrentUserName", you'd do
something like this when the user tried to open the "Accounting" form:

Dim rst As DAO.Recordset
Set rst = Currentdb.OpenRecordset("SELECT * FROM MyPermissionsTable WHERE sTableName='Accounting' AND sUserName='" &
CurrentUserName & "')"

If Not(rst.EOF and rst.BOF) Then
If rst("bAllow") = True Then
'/allow the user to continue
Else
Msgbox "You don't have permission to open the Accounting form"
End If
Else
MsgBox "You don't have permission to open the Accounting form"
End If

set rst = Nothing

You'd need to change the table, column, and variable names to match those in your application, however that's the basic
concept.

Scott McDaniel
scott@takemeout_infotrakker.com
www.infotrakker.com
 
My database structure is very simple:
You open the logon form (Its the same structure used in
http://www.databasedev.co.uk/login.html), then you see a form called
"Entrada" and there you select a button to another form called "Req", and you
work there.
I have a table called "tblEmployees" its where i save users and passwords
(its the same structure used in http://www.databasedev.co.uk/login.html).
I dont know if this help.
Click to expand...

Okay, good start, but you've still got to store information on which users can open which objects. Access stores all
object names in MSysObjects, so you can use that if you like, but you've still got to store the "permissions"

I'd suggest a table like this:

tPermissions
---------------------------------
sObjectName Text, 255 chars (name of the Form, Report, etc)
sUserName Text, 50 chars (name of the user)
bCanOpen Yes/No field (True=User can open)

I'd add a Unique Index with sObjectName and sUserName as the fields, but that's not required.

Next, you'd need to populate that table. For example, let's say you have Users Sue, Sam, and Bob and you want to protect
the Forms frmAccounting, frmEmployees, and frmAdmin

tPermissions
---------------------------------
sObjectName sUserName bCanOpen
frmAccounting Sue T
frmAccounting Sam T
frmEmployees Sam F
frmEmployees Bob T
frmEmployees Sue F
frmAccounting Bob F
frmAdmin Bob F
frmAdmin Sue T
frmAdim Sam F

Next, after logging in the users, you'd then add code to check the permissions for each user as they move through the
database. Depending on how your db is strucutred, you might add this code in your Switchboard, or you might add it in
the Load or Open event of the Form. I'd opt for the Open event, as it can be cancelled:

'/in the code module for frmAccounting, for example
Private Sub Form_Open(Cancel As Integer)
Cancel = UserCanOpen(Me.Name, gUserName)
End Sub

This assumes that you have a variable named "gUserName" which is storing the name of the currently logged in user ... if
you don't then you'd need to change that to provide that username ... I haven't downloaded th sample from the link you
provided, so I don't know how it's being handled but I'll leave that to you.


Add this function to a Standard Module:

Function UserCanOpen(ObjectName As String, UserName As STring) As boolean

Dim rst As DAO.Recordset

Set rst = Currentdb.OpenRecordset("SELECT bCanOpen FROM tPermissions WHERE sObjectName='" & ObjectName & "' AND
sUserName='" & UserName & "')"

If Not (rst.EOF and rst.BOF) Then
UserCanOpen = rst("bCanOpen")
Else
'/if not record is found, allow the user to Open the object
'/Set this to False to disallow
UserCanOpen = True
End If

Set rst = Nothing

End Function

"Scott McDaniel" escreveu:
Click to expand...

Scott McDaniel
scott@takemeout_infotrakker.com
www.infotrakker.com
 
Al users can open all forms. What I want is block all users to delete
registries in forms. Only me like Admin can delete or edit registries.

"Scott McDaniel" escreveu:
 
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