Every SQL Server connection string I ever see looks something like this:
Data Source=MyLocalSqlServerInstance;Initial Catalog=My Nifty Database;
Integrated Security=SSPI;
Do I need the Initial Catalog setting? (Apparently not, since the app I'm working on appears to work without it.)
Well, then, what's it for?
If the user name that is in the connection string has access to more then one database you have to specify the database you want the connection string to connect to. If your user has only one database available then you are correct that it doesn't matter. But it is good practice to put this in your connection string.
This is the initial database of the data source when you connect.
Edited for clarity:
If you have multiple databases in your SQL Server instance and you don't want to use the default database, you need some way to specify which one you are going to use.
Setting an Initial Catalog allows you to set the database that queries run on that connection will use by default. If you do not set this for a connection to a server in which multiple databases are present, in many cases you will be required to have a USE statement in every query in order to explicitly declare which database you are trying to run the query on. The Initial Catalog setting is a good way of explicitly declaring a default database.
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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.
I'm new to SqlServer, right now I have SqlLocalDb installed to work locally. Good, but I can see two connection strings typically and both works:
Data Source=(localdb)\v11.0;Integrated Security=true;
and
Server=(localdb)\v11.0;Integrated Security=true;
What exact difference is there between the two?
For the full list of all of the connection string keywords, including those that are entirely synonymous, please refer to the SqlConnection.ConnectionString documentation:
These are all entirely equivalent:
Data Source
Server
Address
Addr
Network Address
... There is no difference between Server and Data Source as they represent the same thing for SQL Server : the full name of the SQL Server instance with the syntax "MyComputerName\MyShortInstanceName" , potentially including the port used by the SQL Server instance to communicate.
Reference: http://social.msdn.microsoft.com/Forums/en/sqldataaccess/thread/7e3cd9b2-4eed-4103-a07a-5ca2cd33bd21
They are synonymous - you can use either one.
That is - as far as the framework is concerned, they are the same.
My favorite set up is one that doesn't contain any spaces. In the simplest form, one has to provide four values - the URL, the container, the user and the credential.
server
database
user (or uid)
password (or pwd)
So a connection string looks like this.
server=stuffy.databases.net;database=stuffy;user=konrad;password=Abc123(.)(.);
Can I use OPENDATASOURCE (or another mechanism) from a Stored Procedure to connect to the same database as a different user? If so, how?
The database is meant to be deployed to several customers, and replicated by them as many times as they want to, etc. For this reason, I CANNOT HARDCODE the database server's name or the database's name.
(I tried using OPENDATASOURCE, but it only accepts hardcoded connection strings.)
Might EXECUTE AS work in your situation? http://msdn.microsoft.com/en-us/library/ms181362.aspx
You can set up a Linked Server to connect to the remote server using the login's current security context (or other options as it applies to your situation).
From your stored procedure, you could access it with something like SELECT * FROM mylinkedservername.mylinkedserverdatabase.dbo.mytable
But you say you want to connect to the same database but using a different login? You're looking for impersonation. Perhaps you can do this making a Linked Server that references itself, I haven't tried it. Search Microsoft Help documentation for how to set it up normally and test if it does what you're looking to do.
A while ago, I wrote a web-based guestbook application that wrote it's own database.
My code was very amateurish, but, as it was my very first publication, I was very happy with it.
Only about a month after I'd published it did I realize I'd made a huge mistake in the code.
I've only ever connected to a specific named instance of SQL Server, and it occurred to me that, if the SQL Server instance has a different name than the one I specified, it wouldn't work.
So, since my users will probably not know what the name of the instance of SQL Server that's running is, I thought adding a field where the user can specify it would help if they do, but what if they don't?
My answer was to get the local instance, regardless of name.
I tried Data Source=.\local;, Data Source=.; and other variants, but nothing worked.
Any ideas?
A non-named instance is called "default instance" and can be accessed using "Data Source=(local);...".
The only way of knowing which instances are running is by querying the SQL Browser Service, if it's running.
I guess most of your users are running SQL Server Express? If so, the service is called local\SQLEXPRESS. If not, it's local or they've named it themselves. So, I would try local\SQLEXPRESS first, then local. If none works, just throw an exception and ask the user to add it themselves.
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"