My organization uses a user-friendly donor database software that stores its data in .mdb tables in the installation folder. The program itself uses a proprietary method of querying that is unfamiliar to me. I'm a bit familiar with SQL and want to access the tables outside of the software to do queries with SQL. The software allows us to use SQL code but we have to pay a lot more money for that feature. So I'm hoping to open the database files myself and do my own querying.
When I make a copy of the .mdb files and open them, I am not prompted for a password. I can see the table names, but when I go to open an individual table, MS Access gives me the error "Could not read definitions; no read definitions persmission for table or query." When I open it in MDB Viewer Plus I get the error "error setting table name:Records cannot be read; no read permission" I open it back up in MS Access and check out the users listed. There is only one user "Admin" and there is not a password set for it. I try to change the permissions for "Admin" to Read/Modify/Administer but it gives me the error "To change permissions for this object you must have administer permission for it."
My question is, how do I get administer permission for the database? Obviously the donor software has a way to open the databases, so how do I bypass that and open them myself?
There should be an associated MDW file in the data directory or possibly in the app's install directory. That is the workgroup file for the database and will need to be used when opening the database.
Odds are if they went to the trouble of setting up a workgroup though that they locked it down so you couldn't do what you want to do.
This is a pretty good step by step for how to open a database with a workgroup file. You can do the same thing in code too.
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I have a stand-alone Windows Form app written in VB.NET that currently connects to a local Access DB (.mdb file) and consumes data from several of the tables. It never writes to nor modifies the DB. I'm trying to figure out how to secure this DB so the user has no access to it. I'm thinking the best way is to store the DB as an embedded resource within the project. However, I can't figure out how to make this work.
I've added the .mdb file to the project resources and set its properties to "Embedded Resource" and "Do not copy." But now how do I reference the DB to create the connection?
Before I used the connection string "Provider=Microsoft.Jet.OLEDB.4.0; Data Source=MyDatabase.mdb"
How do I write the connection string now with reference to an embedded resource?
"I'm thinking the best way is to store the DB as an embedded resource within the project."
This usually relates to old skool security, in the olden days DotNetNuke developers that used Access dBs as their backend actually renamed the .mdb to .resources as you cant download a resource file from the web.
"Would it be better to export the DB to xml or something like that and then use a stream reader as opposed to a database connection?"
No. You cant read an Access file from a stream And an XML dB has even less concurrency support than an Access Database.
If you really need to protect the data, then you've absolutely chosen the wrong data store.
#JohnBustos wrote "Store the DB remotely and have the program access it over the internet."
Please do not do this. If anything put it on a network share and restrict access. Then look at upgrading the access dB to SQL Server.
Yes, I have had the same problem and I converted the database into a XML or even a TXT file that is embedded. It works very fine !
Sorry, I never closed this out.
My solution was even simpler than those proposed. You can add the .mdb file to the project itself and not mess with the whole "Resource" business. Then set the file's Copy to Output property to "Do not copy". So the .mdb gets compiled into the app, but file itself is not available to the user.
I know I used to need these things when (once upon a time) I was an Access developer (Access 97), but do I need a workgroup file to share a backend database with two other users?
I did the split database thing and gave each their own copy of the front-end, and I thought that simply putting the backend part on a shared file location would do it.
The others can read the database and run forms and such, but they can't add rows - I still can.
What am I missing?
I have a windows application written in VB.net. After finishing it I'll setup the program in more than one pc. I want to connect the program in all PCs to one database in another PC using Microsoft Access, and I also want to limit the level of access of the users to the database in my program.
How can I do it? Many thanks.
Access is capable of handling multiple users, however once you get over 3 or 4 concurrent users you will start to notice that MS Access doesn't scale well. Access is designed for the professional but not an enterprise.
Microsoft SQL Server (Express edition is free - upto 4GB space) is designed for a large number of concurrent users.
I also want to limit the level of access of the users to the database in my program.
You can use folder Permissions if you wish to restrict access to the file. Personally in my old VB6 apps that used MS Access I called the file db.resources rather than db.mdb. This is because a.resources file cant be downloaded if it is hosted online (ref DotNetNuke) and also so people dont know which program to open the file in.
If you need role based security you need a enterprise level database such as SQL Server.
I want to connect the program in all PCs to one database in another PC using Microsoft Access.
Here is how you can have two computers share the same database.
a. Choose the main PC that will host the database
b. Host the database in a folder that is shared to the other users
c. Physically go over to the PC that isn't hosting the database, create a text fileon the desktop.
d. Rename the file extension from .txt to .udl and press enter
e. Double clcik the udl file and enter these settings and navigate to the shared folder that hosts the shared database:
f. Once the Test Connection is successful, close the Data Link Properties window.
g. Right click the UDL file on the desktop and choose Open With and open with notepad
h. You will see your connection string:
[oledb] ; Everything after this line is an OLE DB initstring
Provider=Microsoft.ACE.OLEDB.12.0;Data
Source=\\PCName\c$\temp\Database1.accdb;Persist Security Info=False
i. Set the second pc to use the networked connection string.
Access is perfectly capable to handle 2 users connecting to the same database. However this is not the main strenght of Ms-Access. So, if you plan to grow the user base it's better to start from the beginning with SqlServer Express (or MySql).
You don't need to use asp-net for this scenario if the user are on the same local network.
You are only required to prepare a valid connection string to identify the network location where you install the database. Of course, the PC hosting the database should share the network location and give read/write permissions to all users requiring the access to the database. (This could be the most complicated part depending on where you share the database)
I've been asked to find out why a program is failing. I've traced it to a SQL stored procedure. The program passes in the name of a file that the st. proc. presumably tries to read.
However, the SQL server is returning an error indicating that it cannot access the file because access is denied.
My connection string says Integrated Security=SSPI;. I know for sure that the account that I'm logged in with to run the program has access to the file.
How can I find out for sure what user account the SQL server is using to access the file?
The Windows Process Monitor is a good place to start.
http://technet.microsoft.com/en-us/sysinternals/bb896645.aspx
Out of interest what version of SQL, are we talking CLR or just plain ol' sprocs?
It will be using the SQL Server service account to access the file system.
You can look at this article. User USER_NAME to get the SQL Username for the logged in user.
However, it sounds like the problem might be permissions with the FILE, not with the DB. You'll want to check that the appropraite permissions are set on the File and Directory as well as on the DB.
Recently I inherited a database from another programmer (created / stored with SQL Management Studio 2008), and I am having massive difficulties accessing, modifying, or even viewing the previously created databases.
Specifically, when I try to load one of the databases in SQL Management Studio I get the following error message:
"The database [database name] is not
accessible. (Object Explorer)"
I am connecting to the SQL server with windows authentication.
Anyway, is this a permissions issue left over from the last dev? (he's unavailable, unfortunately) And is there an easy work-around short of completely reinstalling SQL Management Studio?
Edit: Update:
Upon trying to access User Mapping, as suggested below, I got the following error message:
"One or more databases are inaccessible and will not be displayed in list."
Unfortunately, none of the databases I am trying to access appeared in the list, so I assume they are still inaccessible.
It could very well be a permissions problem. If you open Object Explorer in SQL Server Management Studio and expand the Security node (the one under the server instance, not the Security tab under the individual databases) and then expand the Logins node you'll see the list of logins that have been created on the server. Have a look at the properties of each of those and check out the User Mapping information. You'll be able to see which logins are mapped to which databases. It's possible the previous programmer only granted access to the database to certain logins. If you find a login that's mapped to the database you want, try changing the password of the login and then connecting to the database with that login and password. NOTE: be careful when changing the password as it may affect production applications that are using that login and password!
This message:
"One or more databases are inaccessible and will not be displayed in list."
Means that the user you are using right now cannot access to that db. If you can enter with a user that does have access and from that user change your actual user's rights through User Mapping, then you will see it.
You need a dba (or someone with dba equivalent access) to give you rights to the database.