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SQL Server Connection Strings - dot(".") or "(local)" or "(localdb)"
(1 answer)
Closed 5 years ago.
I have several SQL servers in my system:
2017 MSSQLSERVER
2008 SQLEXPRESS
In SSMS I see them like:
GM\
GM\SQLEXPRESS
If I need to connect to SQLEXPRESS I use connection string with . in Server:
connectionString="Server=.;Database=LearnCSharp;Integrated Security=True"
But what does . means in my case and what should be placed in connection string in order to connect to 2017 MSSQLSERVER?
UPD.:
. connects to 2017 server. I have noticed that before computer restart it was connecting to 2008 server
GM connects to 2017 server.
.\MSSQLSERVER generates exception in my application;
System.Data.SqlClient.SqlException (0x80131904): A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 25 - Connection string is not valid) ---> System.ComponentModel.Win32Exception (0x80004005): The parameter is incorrect
.\SQLEXPRESS and GM\SQLEXPRESS - both connects to server 2008
It means localhost or "this machine"
To specify an instance name, use a backslash after the dot (or computer name):
.\SQLEXPRESS
YOURCOMPUTER\SQLEXPRESS
OTHERCOMPUTER\SQLEXPRESS
etc
Remember when this app is deployed to another machine, the value of "this machine" changes. This may or may not be what you want, so watch for it in future
It's also worth noting that the default SQL Server instance cannot be referenced by name, and if you try to give its name the connection won't work out. If you know you want to connect to the default SQL Server instance (whichever one that is, and there can be only one) then don't put a slash or a name, just a reference to the machine:
.
YOURCOMPUTER
etc
The dot is simply an abbreviated way of referencing your local machine and as highlighted in the following ".\MSSQLSERVER" should do it: SQL Server Connection Strings - dot(".") or "(local)" or "(localdb)").
Related
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Provider named pipes provider error 40 could not open a connection to SQL Server error 2 [duplicate]
(9 answers)
Closed 3 years ago.
Hi I'm writing a simple console application to save XML data into the database using bulkcopy but am currently having problems connecting to my database.
I am getting a SqlException error:
A network-related or instance-specific error occurred while
establishing a connection to SQL Server. The server was not found or
was not accessible. Verify that the instance name is correct and that
SQL Server is configured to allow remote connections. (provider: Named
Pipes Provider, error: 40 - Could not open a connection to SQL Server)
I have checked for issues ensuring my SQL server is running and that it's configured correctly. Below is my connection string.
string connectionString = #"Data Source=SYAZANA;Initial Catalog=WangSCM;integrated security=true;" ;
I'm at my wits ends trying to figure out the error, what is the mistake that I'm making?
Follow the steps:
*Go to SQL Server Configuration manager
*SQL Server Network Configuration:
*Protocol for MSSQLSERVER
*In the right pane split page you will have to disable VIA as follows
--->Shared Memory - Enable
--->Named Pipes - Enable
--->TCP/IP - Enable
--->VIA - Disable
Or Try the following
Go to Start -> in search type Services.msc. There you will find services which are available in your system.
There look for -> SQL EXPRESS / SQL Server (SQLEXPRESS) -> Right click on it -> then Start it .
If it is already in Start. Just Stop and start or simply Restart it.
I had the same problem and for some reason I had to add the standard SQL port (1433) and then everything worked again. In your case that would be:
string connectionString = #"Data Source=SYAZANA,1433;Initial Catalog=WangSCM;integrated security=true;"
I have a database called Library created in SQL Server 2014 under my locally created server instance. I am using that database as the datasource in my windows form application. It is working perfectly when on my computer, but when I run it on other machines, it stops with the error
Unhandled exception occurred...
A network-related or instance-specific error occurred while
establishing a connection to SQL Server. The server was not found or
was not accessible. Verify that the instance name is correct and that
SQL Server is configured to allow remote connections. (provider: Named
Pipes Provider, error: 40 - could not open connection to SQL Server)
I have started all services from configuration manager and have enabled tcp/ip under protocols for MSSQLSERVER. Is there any way I can accomplish this, or do I have to shift to local db?
Make sure that your connection string includes your remote machine name as part of the "Data Source", so something like :
connectionString="Data Source=machinename\SQLExpress;Initial Catalog=mydbname;Integrated Security=True"
note that this connection string will target a db name "mydbname", under the machine machinename which has a SQL Express instance.
if that didn't work let me see your connection string.
I can connect asp.net applications to my databases in SQL Server 2008, however when I try to do the same from Visual Studio in a Winforms application, I always get the error:
A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified)"
I use the connection string:
SqlConnection Conn = new SqlConnection(#"Server=.\\myserver address\user;Database=testDatabase");
and I get an error when my form loads as that is when I start the connect.
I have gone to my SQL Server Configuration Manager and I get this:
So I do not know what I am doing wrong. There are previous files for older versions of SQL Server in the program files however I do not see how they could affect it...
My sql services
I would also like to add that I added sql server to the firewall exceptions already
You should consider using connection with following syntax
Server=myServerName\myInstanceName;Database=myDataBase;User Id=myUsername;
Password=myPassword;Integrated Security=SSPI;
OR
Server=myServerName\myInstanceName;Database=myDataBase;Integrated Security=true;
When using current Windows account credentials
OR on local Server with default Windows authentication
Server=myServerName;Database=myDataBase;Integrated Security=true
(this was solution that worked for OP)
And for #"Server=.\\myserver using # before string means that no character would escape that string so
\\ without # turns into \
\\ with # stays \\
check C# '#' before a String
For more information about connection strings please visit connectionstrings.com
Check whether these services has been started or not as shown in below snapshot
..
If then try to start them and please try to connect your database.
Please try to use the folowing command:
I can see that you may have a problem with MOF.
mofcomp.exe "C:\Program Files (x86)\Microsoft SQL Server\100\Shared\sqlmgmproviderxpsp2up.mof"
i have finished a desktop c# project in which i make use of Entity framework 5 and SQL server 2008
in my machine it's working well, but i created a virtual machine and tried to deploy it there and I have problems.
I get this error : System.Data.EntityException: The underlying provider failed on Open. --->
System.Data.SqlClient.SqlException: A network-related or instance-specific error occurred while establishing a connection to SQL Server.
The server was not found or was not accessible.
Verify that the instance name is correct and that SQL Server is configured to allow remote connections.
I used installshield for the setup and I have installed sql express in the visrual machine, during the setup I create the database and all the tables.
my connection string is this :name="BussinessContainer" connectionString="metadata=.\Bussiness.csdl|.\Bussiness.ssdl|.\Bussiness.msl;provider=System.Data.SqlClient;provider connection string="data source=localhost;initial catalog=yingyangDB;User ID=username;Password=password;integrated security=True;MultipleActiveResultSets=True;App=EntityFramework"" providerName="System.Data.EntityClient"
Should I change the connection string?
I searched a lot before posting this, but nothing worked..any help?
SQL Express (normally) doesn't create as a "Default instance" - i.e. connecting by localhost isn't sufficient to connect to the local SQL express instance.
You may need to use localhost\SQLExpress to connect to the local SQL Express instance (the instance name may be different, but usually it is not.
Additionally, you specify an Initial Catalog in your connection string, which I assume is pointing at your new DB. However you say that you create the DB during the installation - so that DB may not actually exist in your Instance yet. That may be causing it to fail out. Try taking it out of the string and see if that lets you connect.
I am using VSTS 2008 + .Net 3.5 + C# + SQL Server 2008 Enterprise on Windows Server 2003. I am using the following connection string, and labtest1 is the local machine name and I connect from local machine using ADO.Net. Then it always fail with connection error. But when I change in the connection string from "labtest1" to ".", connection has no issue with the same ADO.Net client code. Any ideas what is wrong?
Data Source=labtest1;Initial Catalog=CustomerDB;Trusted_Connection=true;Asynchronous Processing=true
Here is the detailed error message I got,
System.Data.SqlClient.SqlException: A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server)
Looks like a Sql Server configuration issue to me : have you tried to tune protocols in Sql Server Network configuration ? Named Pipes or TCP/IP should be enabled.
When you use "." or "(local)" it connects to the default instance on your PC, perhaps the SQL Server was installed with instances, in which case you have to specify the instance name in the connection string in the format "SERVER\INSTANCE_NAME".
In SQL Management studio execute this query to see your full server\instance name
select ##servername
I have seen this issue previously with ZoneAlarms blocking the connection (on the machine trying to connect to the SQL server). I would spend some time investigating this area around firewalls etc.
Hope this helps
Do you have the Named Pipes network protocol enabled in the network config? (In the SQL Server Configuration Manager - sql server 2005, that's what I have, might be different in 2008 - you should be able to verify this setting)
Try to ping by the computer name: ping labtest1. if it does not find the server, then try ping labtest1.mydomainname.com with the domain name. If this works, then you just need to add/fix the DSN aliases in the domain controller or just re-login to the machine.
One other thins - and may not be relevant - but you've not specified the security model, at least not in the string provided as a sample.
I would expect to see: Integrated Security=True (given that its the local machine) in the connection string.
The other thing that may be relevant is - as has already been mentioned - the protocols, I'd look to make sure that TCP/IP is enabled.