Connecting to SQL Server in a remote server from Access - sql-server

We have a Server A and a Server B.
In Server A we have our ERPs made in Access and VBA.
In Server B we have an instance of SQL Server that needs to stay in that server.
Some Access databases need to link to some tables from that SQL Server instance and I don't want the password to be stored in the MSysObjects table, so I cannot manually link the tables checking the save the connection option.
I saved the connection string in a table with password obfuscation. With that connection string I re-link the tables on startup.
The instance is accessed through it's IP, not the name of the instance. If I use the name of the instance it doesn't work.
It works for me but not for other users except one.
The SQL Server instance has been properly configured to allow remote connections, the ports have been opened and rules added to firewall. If it wasn't properly configured it wouldn't work for me and the other user, so I'm pretty confident in that. The same with the connection string and the methods to stablish the connection in Access.
What I've tried:
Installing the SQL Native Client 11.0.
Installing a full SQL Server Express.
Configured the SQL Browser service to star automatically instead of being disabled.
Step 1 did not work for any user. Step 2 did work for one user but not for the rest. Step 3 did not had any effect. For me I had it installed in my machine since forever, so it doesn't apply.
If I try to do the same with a SQL Server instance in our LAN it works for every user, but not when the instance is in a remote server.
Note I have limited knowledge. Maybe I say something that does not make sense.

Ok, a few things:
Installing the SQL Native Client 11.0.
Ok, then you have to re-link the tables - choose the new driver. A refresh of the linked tables is NOT sufficent. And this ALSO means that each work station ALSO now must have native 11 instlled. And if you say decide to link using native 17 (a much newer odbc driver), then AGAIN YOU must install this native driver on each work station. While you can install multiple sql drivers on each workstation, the driver you used to link the tables MUST ALSO be installed and exist on each work station.
Installing a full SQL Server Express.
Why? What would installing a copy of sql server have to do with OTHER sql servers on other machines that you are attempting to connect to? You think installing sql server on a machine effects the sql server running say on amazon.com? So, this move makes no sense at all.
You are attempting to connect to some instance of sql server running on some other computer. Makes no sense nor will it help to install some copy of sql server that you not using, not connecting to, and that has zero to do with this issue.
Configured the SQL Browser service to star automatically instead of being disabled.
Where? The browser service is set to run and startup on the server and SAME machine where sql server is installed and running. So, yes, without question, those two sql servers A, and B most certainly MUST have the sql browser service running. That service is what allows the client computers to connect to that running instance of sql server. In the past, older (previous) versions of sql server would allow a default connection, but now in near all cases, you MUST ensure that the sql browser service is running on that computer that also has the database you are attempting to connect to.
it's worth to note that the instance is accessed through it's IP, not the name of the instance.
No, you likly have this incorrect. There are two part.
The server name - and then the "instance" of sql server running.
While you can swap out (not use) the server name, you STILL WILL NEED to specify the sql server instance.
So, you can use this format:
myservername\SQLEXPRESS
Or, you can replace the server with a IP address, but you STILL NEED the sql server instance. (by default, it is SQLEXPRESS - but you have to check what the instance of sql server database is).
192.168.1.30\SQLEXPRESS
So while you can use IP or server name - it is often more reliable to use the IP address, but that does NOT get you off the hook from having to specify the sql instance you connect to. Again, previous editions of sql server often allowed a "default" instance, and you did not in general have to specify the "instance", but now you do. And to be double clear, when using such a instance, that sql server needs to be running the sql browser service. (in fact, the browser service is what translates the incoming request to the given and correct instance of sql server).
I DON'T want the password to be stored in the MSysObjects table,
You don't have to, and in fact should NOT include the uid/password in your connection string. And in fact ZERO reason exists to do so.
What you do is execute a one time logon, and THEN link the tables without UID/password. This is not only a great idea, but it also means that your uid/password is not included in the connection strings, but also means users can't get at, or even by accident see/get the uid/password.
It also means that say someone where to launch a copy of access, and import the linked tables from this applcation. When they attempt to use the linked tables, they will NOT work.
So, then how do linked tables work without a password? (and this ALSO by the way saves you from having to re-link tables on startup!!!).
The way this works, is you in code execute a one time logon to the server on startup. That means you can either:
Prompt the user for their sql UID/password.
or
Have in code, the uid/password. (or perhaps in a text file y ou read on startup. You can thus hide, or encrypt or whatever for that uid/passwords.
Then in your startup code, you execute a one time logon. Once you done this, then all linked tables will now work - and work without having uid/password.
since you have two servers then you need to execute two logons, one for server A, and one for server B. But, once again, as long as the linked tables exist, then they will work.
Now, there are "longer" articles on how to use this logon idea, and then not have to include, or re-link your tables for the SQL uid/password.
The basic code to execute a logon is like this:
Function TestLogin(strCon As String) As Boolean
On Error GoTo TestError
Dim dbs As DAO.Database
Dim qdf As DAO.QueryDef
Set dbs = CurrentDb()
Set qdf = dbs.CreateQueryDef("")
qdf.connect = strCon
qdf.ReturnsRecords = False
'Any VALID SQL statement that runs on server will work below.
' this does assume user has enough rights to query built in
' system tables
qdf.sql = "SELECT 1 "
qdf.Execute
TestLogin = True
Exit Function
TestError:
TestLogin = False
Exit Function
End Function
Keep in mind, that ONCE you acheived a legal logon, then EVEN addtional logon attempts will return true.
Not usually a big deal, but this means you supply a valid connection to above, and if it logs on and works - then now all your linked tables (without uid/password) will work.
I note the above issue that ONCE you done the logon, then all 2nd or more times running the above will work (even if bad or incorrect!!! - DO NOT forget this tip!!!). (this can confuse the daylights out of a developer, since they execute logon, (or open a table). Then they test above routine with a BAD uid/passwords, and it works!!!
So, you have to EXIT access to clear out the password cache - no other way.
So, keep the above tips in mind.

Related

Database and Dataset data is empty [duplicate]

Apparently, using AttachDbFilename and user instance in your connection string is a bad way to connect to a DB. I'm using SQL server express on my local machine and it all seems to work fine. But what's the proper way to connect to SQL server then?
Thanks for your explanation.
Using User Instance means that SQL Server is creating a special copy of that database file for use by your program. If you have two different programs using that same connection string, they get two entirely different copies of the database. This leads to a lot of confusion, as people will test updating data with their program, then connect to a different copy of their database in Management Studio, and complain that their update isn't working. This sends them through a flawed series of wild goose chase steps trying to troubleshoot the wrong problem.
This article goes into more depth about how to use this feature, but heed the very first note: the User Instance feature has been deprecated. In SQL Server 2012, the preferred alternatives are (in this order, IMHO):
Create or attach your database to a real instance of SQL Server. Your connection string will then just need to specify the instance name, the database name, and credentials. There will be no mixup as Management Studio, Visual Studio and your program(s) will all be connecting to a single copy of the database.
Use a container for local development. Here's a great starter video by Anna Hoffman and Anthony Nocentino, and I have some other resources here, here, and here. If you're on an M1 Mac, you won't be able to use a full-blown SQL Server instance, but you can use Azure SQL Edge if you can get by with most SQL Server functionality (the omissions are enumerated here).
Use SqlLocalDb for local development. I believe I pointed you to this article yesterday: "Getting Started with SQL Server 2012 Express LocalDB."
Use SQL Server Compact. I like this option the least because the functionality and syntax is not the same - so it's not necessarily going to provide you with all the functionality you're ultimately going to want to deploy. Compact Edition is also deprecated, so there's that.
Of course if you are using a version < SQL Server 2012, SqlLocalDb is not an option - so you should be creating a real database and using that consistently. I only mention the Compact option for completeness - I think that can be almost as bad an idea as using AttachDbFileName.
EDIT: I've blogged about this here:
Bad Habits : Using AttachDBFileName
In case someone had the problem.
When attaching the database with a connection string containing AttachDBFile
with SQLEXPRESS, I noticed this connection was exclusive to the ASP.NET application that was using the database. The connection did block the access to all other processes on the file level when made with System.Data.SqlClient as provider.
In order to assure the connection to be shareable with other processes
instead use DataBase to specify the database name in your connection string
Example or connection string :
Data Source=.\SQLEXPRESS;DataBase=PlaCliGen;User ID=XXX;password=ZZZ; Connect Timeout=30
,where PlaCliGen is the name (or logical name) by which SQLEXPRESS server knows the database.
By connecting to the data base with AttachDBFile giving the path to the .mdf file
(namely : replacing DataBase = PlacliGen by AttachDBFile = c:\vs\placligen\app_data\placligen.mdf) the File was connected exclusively and no other process could connect to the database.

How to avoid prompting for user id and password in MSAccess 2003

I am a .Net / SQL Server programmer. I am trying to make an Access database created by someone else to work. It looks like is uses a procedure similar to Save password for ODBC connection to SQL Server from MS Access 2007 but I am using Access 2003 so I suspect something else needs to be done. I don't really know what I am doing with Access but I am stuck with it.
I do have an ODBC connection and it looks like the linked tables use it. The database has an AutoExec which populates some local tables from the linked tables that the reports use. It also calls a qryConnect with a dsn-less connection like the linked article and this seems to work. I have got it to stop asking for a user and password on start up. I can also open most reports without problems, 2 do not work. A form loads on Startup with buttons that basically show reports. This is where it gets odd.
The reports fail from the ODBC driver with the windows credentials. Then a logon box shows up with the correct user (a user with read only privileges) but the trusted connection box is checked. I do not have the trusted box checked in the DSN. Not do I have Trusted_Connection=Yes in the DSN-less connection in qryConnect.
This is the code in the form
stDocName = "rptNegativeLotQtys"
DoCmd.OpenReport stDocName, acPreview
I don't know how I buggered it up so much and before I try again copying everything to a new mdb and trying again I am hoping to get some guidance.
On a side note I can open everything fine on my machine. I am an administrator as far as Windows is concerned but not SQL Server.
EDIT:
I created a new DSN just for these reports. Then I deleted all linked tables and re-linked then using the new DSN. I looked at the linked tables in MsysObjects and the new DSN is listed there. Yet Access still prompts for the password. It appears that it is not caching the password.
Actually, you do NOT need to add nor store the UID/Pass in the connection strings used. However, what you MUST ensure is that all connection strings are the SAME. If they are different, then the cached UID/password will not work.
Also, make sure you do NOT connect nor open a table AFTER having connected using Windows Auth – the reason being then when you add the table links (especially via code), then the cached setup of using windows auth will occur, and thus prompts will occur when the links suggest to do otherwise. In other words linking and attempted to use SQL logons will NOT work if you already opened any table link via windows auth (so exit the database and do NOT open any table that could/can use windows auth).
So I would delete the links, and re-create them – but again, ensure that you never connected as a windows auth user to SQL server.
So the "cache" that access has is a GREAT friend/feature to eliminate the need to include UID/pass in the connection string - but the SAME feature will bite you VERY bad if you at any time connecte to the database in question via windows auth.
How to “cache” the user logon and ID is explained here:
Power Tip: Improve the security of database connections
http://blogs.office.com/b/microsoft-access/archive/2011/04/08/power-tip-improve-the-security-of-database-connections.aspx
So you “can” include the UID/LOGON in the linked tables, but above shows that a ONE time logon can also be used. So be VERY careful when setting up table links – due to the above “cache” of the user and HOW they logged into the database – code that ATTEMPTS to create table links based SQL logons will actually wind up using windows auth if you already connected as such (so exit the database if you going to re-link using SQL logons).
Keep in mind, Access does NOT use the DSN AFTER you linked the table. The information from the DSN is a ONE TIME copy to the connection string. You can verify this by going into my documents and deleting the DSN you used. Assuming the linked table was working correctly, you find that they CONTINUE to work EVEN if you delete the DSN. In effect this means that linked tables are DSN less except for when you create the linked table. This allows you to easy copy the application to different computers without having to copy the DSN.
As to ensure that all the linked tables use the same connection string, it is a simple matter to delete them all, and re-link.
You can also hit ctrl-g to bring up the debug window, and look at the connection string this way:
? currentdb.TableDefs("linked table name").Connect
the result in the debug window for a windows auth connection string will look like this:
ODBC;Description=test DSN;DRIVER=SQL Server;
SERVER=albertkallal-pc\SQLEXPRESS;
Trusted_Connection=Yes;
APP=Microsoft Office 2010;DATABASE=AxisMIS
Note how in above we see "trusted connection" (that means windows auth).
If I linked the table using SQL logon (and REMEMBER to check save password), then you see this:
ODBC;Description=TEST3;DRIVER=SQL Server;
SERVER=ALBERTKALLAL-PC\SQLEXPRESS;
UID=MySQLogon;PWD=MyPassword;
APP=Microsoft Office 2010;DATABASE=AxisMIS
Just remember during the table link process to "check" the save password.
eg this:

finding the correct connection string for a local SQL instance

I'm trying to build a connection string for a test environment that will connect to the local SQL Server instance on different machines. The purpose of this is so that a developer can checkout the code from TFS, build it, and run the testcases, connecting to his local DB. The problem is that different developer's machines may have different SQL Server setups. In particular, some may be running the full server, others may be running SQL Server Express.
I'm trying to right a utility routine that will take template connection string (e.g., Data Source=(local); Initial Catalog= myDB; Integrated Security=SSPI;) and modify the Data Source to work with the local server.
I've tried using SmoApplication.EnumAvailableServers() (returns an empty table, regardless of whether I user true or false parameters), and SqlDataSourceEnumerator.GetDataSources() (returns 2888 servers from the network, but none on the local machine), SQLCMD -L (returns nothing).
Any suggestions?
In the alternative, is there an easy way to tell whether a particular connection string will connect to a server (without waiting for it to timeout if it doesn't). If I could find the answer to that, I could try the likely suspects until I got one to work.
you might try to get the connection string as following:
Create a new blank file and name it test.udl.
Double click on it, and a "Data Link Properties" dialog should appear.
On "Providers" tab, select "Microsoft OLE DB Provider for SQL Server" or "SQL Native Client"
On "Connections" tab, try various settings and use the "Test Connection" button to test them. Click "Ok" when it works.
Open the test.udl file in Notepad and copy the line that starts with "Provider=" into your Web.config "ConnectionString" value, BUT delete the little part that says "Provider=SQLNCLI.1;"
If you want each developer to work with their own local SQL server, then the ADO connection string should have the Data Source set to localhost
... ; Data Source=localhost; ...
Additionally, to get a list of current servers, go to the command line and run
osql -L
You can look in the registry to find all local SQL Server instances. This key contains the list: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\Instance Names\SQL.
Each named instance will have a value in this key. For named instances the name of the value is the same as the name of the instance. For the default instance the value will be named MSSQLSERVER.
This will do the trick:
Data Source=.\SQLEXPRESS

Mirroring in SQL Server 2008

I'm trying to set up mirroring between two sql 2008 databases on different servers in my internal network, as a test run before doing the same thing with two live servers in different locations.
When I actually try and switch the mirroring on the target DB (with
ALTER DATABASE testdb SET PARTNER = N'TCP://myNetworkAddress:5022') I'm getting an error telling me that the server network address can not be reached or does not exist. A little research suggests this is a fairly unhelpful message that pops up due to a number of possible causes, some of which are not directly related to the server existing or otherwise.
So far I've checked and tried the following to solve this problem:
On the target server, I've verified that in SQL Configuration Manager that "Protocols for SQLEXPRESS" (my local installation is labelled SQLEXPRESS for some reason, even though querying SERVERPROPERTY('Edition') reveals that it's 64-bit Enterprise), and Client Protocols for SQL Native Client 10 all have TCP/IP enabled
I'm using a utility program called CurrPorts to verify that there is a TCP/IP port with the same number specified by the mirroring setup (5022) is open and listening on my machine. Netstat verifies that both machines are listening on this port.
I've run SELECT type_desc, port FROM sys.tcp_endpoints; and
SELECT state_desc, role FROM sys.database_mirroring_endpoints to ensure that everything is set up as it should be. The only thing that confused me was the "role" returns 1 .. not entirely sure what that means.
I've tried to prepare the DB correctly. I've taken backups of the database and the log file from the master DB and restored them on the target database with NORESTORE. I've tried turning mirroring on both while leaving them in the NORESTORE state and running an empty RESTORE ... neither seems to make much difference. Just as a test I also tried to mirror an inactive, nearly empty database that I created but that didn't work either.
I've verified that neither server is behind a firewall (they're both on the same network, although on different machines)
I've no idea where to turn next. I've seen these two troubleshooting help pages:
http://msdn.microsoft.com/en-us/library/ms189127.aspx
http://msdn.microsoft.com/en-us/library/aa337361.aspx
And as far as I can tell I've run through all the points to no avail.
One other thing I'm unsure of is the service accounts box in the wizard. For both databases I've been putting in our high-level access account name which should have full admin permissions on the database - I assumed this was the right thing to do.
I'm not sure where to turn next to try and troubleshoot this problem. Suggestions gratefully received.
Cheers,
Matt
I think that SQL Express can only act as a witness server with this SQL feature, you might get better mileage on ServerFault though.
Mike.
Your network settings might be OK. We got quite non-informative error messages in MS SQL - the problem might be an authorization issue and the server still will be saying "network address can not be reached".
By the way, how the authentication is performed? A MSSQL service (on server1) itself must be runned as a valid db user (on server2, and vice versa) in order to make the mirroring work.

SQL Server, convert a named instance to default instance?

I need to convert a named instance of SQL server 2005, to a default instance.
Is there a way to do this without a reinstall?
The problem is, 2 out of 6 of the developers, installed with a named instance. So its becoming a pain changing connection strings for the other 4 of us. I am looking for the path of least resistance to getting these 2 back on to our teams standard setup.
Each has expressed that this is going to be, too much trouble and that it will take away from their development time. I assumed that it would take some time to resolve, in the best interest of all involved, I tried combing through configuration apps installed and didn't see anything, so I figured someone with more knowledge of the inner workings would be here.
I also wanted to convert a named instance to default - my reason was to access it with just the machine name from various applications.
If you want to access a named instance from any connection string without using the instance name, and using only the server name and/or IP address, then you can do the following:
Open SQL Server Configuration Manager
Click SQL Server Network Configuration
Click Protocols for INSTANCENAME you want to make available (i.e. SQLExpress)
Right-click TCP/IP and click Enabled
Right-click TCP/IP and go to Properties
Go to the IP Addresses tab
Scroll down to the IPAll section
Clear the field TCP Dynamic Ports (i.e. empty/blank)
Set TCP Port to 1433
Click Ok
Go to SQL Server Services
Right-click your SQL Server (INSTANCENAME) and click Restart
This will make the named instance listen on the default port. Note : You can have only one instance configured like this - no two instances can have same port on the IP All section unless the instance is a failover cluster.
As far as I know, no. One reason is the folder structure on the hard drive; they will have a name like MSSQL10.[instancename]
This is why a lot of companies store their applications' connection strings at the machine level instead of the application level.
Just take the connection string out of the source code entirely. Then have everyone put their connection string in their machine.config.
This has the added benefit of avoiding unnecessary app-specific environment logic, i.e. when you copy your application to the staging server, the staging server already "knows" what database to use.
The only way to change the instance name is to re-install - uninstall and install as default instance.
A lot of times I'll use client alias to point an application at a different sql server than the ones it's connection string is for, esp. handy when working on DTS or an application with a hard coded connection string. Have everybody use a commonly named alias, use the alias in the connection string and point the alias’s on each dev box to the to the different instances. That way you won't have to worry about if the server is the default instance or not.
You shouldn't ever really need to do this. Most software that claims to require the default instance (like Great Plains or Dynamics) doesn't actually.
If you repost with your situation (installed X, then Y, but need to accomplish Z) I bet you'll get some good workarounds.
I think you can migrate your data from Sql Server without having default instance installed. You can just specify the port number of your Sql Server instance in Oracle Sql Developer and you can connect just using the server name, not using the server name and the instance.
Like this:
connect to "MYSERVER, 1433"

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