Connecting to SQL Server in Visual C# - sql

I'll show the code I'm using, but I can't connect to SQL Server through Visual C#. I have installed what came in the C# package and I keep getting this error:
An unhandled exception of type 'System.Data.SqlClient.SqlException' occurred in System.Data.dll
Additional information: 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 can't figure out how to connect to the server. I'm using Windows 8, SQL Sever 2012 (Visual Studio 2012) and if I go to connect in the top toolbar, it doesn't matter if I use (local), localhost or my IP address. I can't figure this out and its driving me nuts! Here's my code, if it helps.
private void btnSave_Click(object sender, EventArgs e)
{
System.Data.SqlClient.SqlConnection sqlConnection1 =
new System.Data.SqlClient.SqlConnection("Server=(local);Database=Database1DataSet;Trusted_Connection=True;");
System.Data.SqlClient.SqlCommand cmd = new System.Data.SqlClient.SqlCommand();
cmd.CommandType = System.Data.CommandType.Text;
cmd.CommandText = "INSERT VALUES (id, Medname, MedDose, MedAm, MedNoon, MedEve, MedNight, MedPRN, MedOther) VALUES (1, 'Clonazepam', '2mg', 'true', 'true', 'false', 'true', 'true', 'false')";
cmd.Connection = sqlConnection1;
sqlConnection1.Open();
cmd.ExecuteNonQuery();
sqlConnection1.Close();
}
Thanks so much. This is my first time using SQL Server through Visual Studio.

If you installed SQL Server as part of the Visual Studio 2012 install process, then it installed SQL Server Express LocalDB. LocalDB is very lightweight and does not have a constantly running service. If you actually did install LocalDB while installing Visual Studio, you should be able to see the "instance" by going to the View menu in Visual Studio and selecting SQL Server Object Explorer. There should be a folder (so to speak) for "SQL Server" and expanding that should show you something along the lines of:
(localdb)\V11
or
(localdb)\Projects
Whatever that value is, THAT is what you specify for the "server=" in the connection string. So, your connection string should look more like this (due to the backslash, you should prefix the string with #):
#"Server=(localdb)\V11;Database=Database1DataSet;Trusted_Connection=True;"
Also, when you create a new project in Visual Studio, it should pre-populate the correct connection string in the Debug tab of Project Properties.
EDIT:
Also, you can find the instance name(s) in the following location as each instance will be a subfolder:
C:\Users\{YourUserName}\AppData\Local\Microsoft\Microsoft SQL Server Local DB\Instances

Related

R Shinyapp connects to server fine but on publishing driver is incorrect

So my Shinyapp works great locally connecting to my Azure Server housing my SQL database using this connection:
con <- DBI::dbConnect(odbc::odbc(),
driver="SQL Server",
database="<db>",
UID="<user#db>",
PWD="<password>",
server="tcp:<user>.database.windows.net",
port=1433)
When publishing, I get this error:
nanodbc/nanodbc.cpp:950: 01000: [unixODBC][Driver Manager]
Can't open lib 'SQL Server' : file not found
http://docs.rstudio.com/shinyapps.io/applications.html suggests to use SQLServer instead of SQL Server but the connection breaks down (both from locally and when publishing).
I've also tried the RODBC but this has not worked either.
I'm a bit stumped on what driver to use to make the connection work. Any help would be greatly appreciated!

Failing VB.NET OleDbConnection. SQL Server does not exist or access denied

Realise this has been asked before but i have been unable to find a solution that works in this case.
I am trying to connect to a sql database over a network. The server is 2008 and the application is VB.Net (4).
The offending script is;
Dim strConnection As String = "Provider=SQLOLEDB.1;Persist Security Info=False;User ID=XXXX;Password=XXXX;Initial Catalog=MBB;Data Source=NETPC\SQLEXPRESS"
con = New OleDbConnection(strConnection)
con.Open()
The user id and password connect and has write permission to the db
using SQL Management Studio.
I have tested the connection string using the .udl quick test where
it worked fine and matched the string above.
The db is set up to accept both windows & sql server (password
protected) authentication.
Actual error is;
An unhandled exception of type 'System.Data.OleDb.OleDbException'
occurred in System.Data.dll Additional information:
[DBNETLIB][ConnectionOpen (Connect()).]SQL Server does not exist or
access denied.

Error message: (provider: Shared Memory Provider, error: 0 - No process is on the other end of the pipe.)

I am trying to deploy my website on windows server 2003.
Am i missing something or what is wrong from the following error message, how can I correct it? Thank
I am having the error message:
A connection was successfully established with the server, but then an error occurred during the login process. (provider: Shared Memory Provider, error: 0 - No process is on the other end of the pipe.)
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.Data.SqlClient.SqlException: A connection
was successfully established with the server, but then an error
occurred during the login process. (provider: Shared Memory Provider,
error: 0 - No process is on the other end of the pipe.)
Source Error:
An unhandled exception was generated during the execution of the
current web request. Information regarding the origin and location of
the exception can be identified using the exception stack trace below.
Stack Trace:
[SqlException (0x80131904): A connection was successfully established
with the server, but then an error occurred during the login process.
(provider: Shared Memory Provider, error: 0 - No process is on the
other end of the pipe.)]
System.Data.ProviderBase.DbConnectionPool.GetConnection(DbConnection
owningObject) +1019
System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection
owningConnection) +108
System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection
outerConnection, DbConnectionFactory connectionFactory) +126
System.Data.SqlClient.SqlConnection.Open() +125
NHibernate.Connection.DriverConnectionProvider.GetConnection() +104
NHibernate.Tool.hbm2ddl.SuppliedConnectionProviderConnectionHelper.Prepare()
+15 NHibernate.Tool.hbm2ddl.SchemaMetadataUpdater.GetReservedWords(Dialect
dialect, IConnectionHelper connectionHelper) +89
NHibernate.Tool.hbm2ddl.SchemaMetadataUpdater.Update(ISessionFactory
sessionFactory) +80
NHibernate.Impl.SessionFactoryImpl..ctor(Configuration cfg, IMapping
mapping, Settings settings, EventListeners listeners) +599
NHibernate.Cfg.Configuration.BuildSessionFactory() +104
MyProject.API.Data.SessionManager..cctor() in
C:\Dev\Code\API\Data\SessionManager.cs:27
Typically, to troubleshoot this, you go to SQL Server Configuration Manager (SSCM) and:
ensure Shared Memory protocol is enabled
ensure Named Pipes protocol is enabled
ensure TCP/IP is enabled, and is ahead of the Named Pipes in the settings
Maybe it can help: Could not open a connection to SQL Server
Note : If this is a new instance of SQL Server be sure SQL Server and Windows Authentication is enabled
Right Click the Server in SSMS and pull up server properties
Go to Security--> Select 'SQL Server and Windows Authentication Mode'
Restart the Server and Login with the credentials
Check if your connection string has "Trusted_Connection=true" added.
I had this same error message, turns out it was because I didn't have mixed mode auth enabled. I was on Windows Auth only. This is common in default MSSQL deployments for vSphere, and becomes an issue when upgrading to vSphere 5.1.
To change to mixed mode auth you can follow the instructions at http://support.webecs.com/kb/a374/how-do-i-configure-sql-server-express-to-enable-mixed-mode-authentication.aspx.
I had the same error by in SQL Server Management Studio.
I found that to look at the more specific error, look at the log file created by the SQL Server. When I opened the log file, I found this error
Could not connect because the maximum number of ’2′ user connections
has already been reached. The system administrator can use
sp_configure to increase the maximum value. The connection has been
closed
I spend quite some time figuring this out. Finally running the following code fixed my problem.
sp_configure 'show advanced options', 1;
go
reconfigure
go
sp_configure 'user connections', 0
go
reconfigure
go
More on here and here
Edit
To view logs search for "logs" on windows startup button, click "view events logs". From there go to Applications under "Windows Logs". You can also choose "System" logs to see system wise errors. You can use filter on current logs by clicking "Filter Current Logs" on right side and then select "Error checkbox".
Just another possibility. I had to restart the sql server service to fix this issue for me.
The "real" error was in the SQL error log:
C:\Program Files\Microsoft SQL Server\MSSQL14.MSSQLSERVER\MSSQL\log\ERRORLOG
Path will depend on your version of SQL Server
You should enable the Server authentication mode to mixed mode as following:
In SQL Studio, select YourServer -> Property -> Security -> Select SqlServer and Window Authentication mode.
Goto to SQL server using windows Credentials - > Logins - > Select the Login - > in the Properties -> Check if the Log in is enabled/disabled.
If Disabled, make it enable, this solution worked for me.
Adding this to my connection string worked for me:
Trusted_Connection=true
In C# and SQL SERVER, we can fix the error by adding Integrated Security = true to the connection string.
Please find the full connection string:
constr = #"Data Source=<Data-Source-Server-Name>;Initial Catalog=<DB-Name>;Integrated Security=true";
By looking into SQL SERVER log file in "C:\Program Files\Microsoft SQL Server\MSSQL13.MSSQLSERVER\MSSQL\Log\ERRORLOG", it says
"Login failed for user 'XXXXX'. Reason: An attempt to login using SQL authentication failed. Server is configured for Windows authentication only. [CLIENT: ]"
The fixing method is to open "Microsoft SQL Server Management Studio" -> Right click the SQL server and then select "Properties" -> Security -> Change the authentication to mixed mode. -> Restart SQL server.
I was getting this error today. In my case, looking at the ERRORLOG file on the SQL server gave me this error:
Login failed for user ''. Reason: Failed to open the
database '' specified in the login properties.
This was because I had deleted the "Default database" of this user a few days ago. Setting the default database to my new database fixed the problem.
Hope this helps someone else.
I forgot to add the "Password=xxx;" in the connection string in my case.
I had the same error, Fixed it by ensuring that SQL server had SQL authentication mode enabled.
see images below.
To enable, go to server properties.
Click on the Security tab and select the SQL server and window server auth mode and press ok
You will need to restart the server for the changes to reflect, should be fine now.
Enable Mixed authentication mode while installing MSSQL server. Also provide password for sa user.
Hi Just enable both for server authentication as per screen shot attached below.
All good and valid courses of investigation especially the logs for more info.
For those hitting this it might be a simple gotcha where when you have created the DB User you may have enforced a password policy and left the user to change the password on first login (i.e. left the checkboxes around the password field at their default values).
Very easily done in SQL Management Studio and can of course cause authentication issues off the bat that are masked unless you look into the logs.
Check that the server name you're logging into with SQL Management Studio matches your connection string.
I was getting this error today.
It turned out that I hadn't realised the machine with SQL Server installed had multiples servers running. I had in fact put my database in a totally different server to the one I thought I was using. (So my connection string was pointing to a server with no database)
Hence, When .net tried to access the database it couldn't find anything and gave only a misleading error message about pipes.
I opened the correct server in SQL Management Studio, added my database to and then all worked fine.
(If the correct server isn't available in the dropdown, try browsing for it.)
In my case it was a spelling mistake in the database name in connection string.
This is old but I had the problem in the connect dialog that it was still defaulting to a database I had removed. And by running those commands the default database in the prompt wasn't changing.
I read somewhere I can't find now, that if you open the "Connect to Server" dialog and then select "Options" and select "Connection Properties" tab by typing the default database (no by selecting from the drop down) the database will then stay on that new value entered. This sounds like a flaw to me but in case someone was wondering about that, that should fix the issue, at least on SQL Server 2012
I know i am probably the only one that will have this problem in this way. but if you deleted the mdf files in the C:/{user}/ directory, you will get this error too. restore it and you are golden
I ran across this in a code-first application which expected the database to be there:
Make sure the database is created / the name in the connection string is correct.
I had the same problem. I tried all the suggested answers in this page but to no avail! Finally, I tried the steps below and it worked for me:
In SQL Server Management Studio Object Explorer, right-click the server, and then click Properties.
On the Security page, under Server authentication, select the new
server authentication mode, and then click OK.
In the SQL Server Management Studio dialog box, click OK to
acknowledge the requirement to restart SQL Server.
In Object Explorer, right-click your server, and then click Restart.
If SQL Server Agent is running, it must also be restarted.
Then try this in your Package Manager Console:
Scaffold-DbContext "Server=YourServer;Database=YourDB;Persist Security Info=False;User=YourUserName; Password=YourPassword; MultipleActiveResultSets=False;Encrypt=False; TrustServerCertificate=False; Connection Timeout=30;" Microsoft.EntityFrameworkCore.SqlServer -OutputDir Models -Context DatabaseContext -f
In my case, my situation was a little different.
1. My Mistake: I was missing a ";" in stringConnection. I know this is a newbie bug, but I am new to C # and SQL Server. I have one day :)
private string connectionString = "Data Source=localhost;Initial Catalog=FundamentalsCSharp"
+ "User=sa;Password=123456";
2. My Solution: Put a ";" it was missing after the phrase "FundamentalsCSharp" and it worked.
private string connectionString = "Data Source=localhost;Initial Catalog=FundamentalsCSharp;"
+ "User=sa;Password=123456";
3. Note: Change "FundamentalsCSharp" for your owned Initial Catalog.
I hope this can be of use to someone. Thanks!
In my case, my project is Asp.net Core 3.1 and this is my connection string
"ConnectionString": "Data Source=.; Initial Catalog=WebDB; user Id=sa; Password=123"
And database name in sql server webdb (lower case in sql server).
After many time change database name webdb in connecion string and worked fine.
For those doing entityframework code first, also check to enture you have done your migrations.
The best place to look for the root cause is the sql server error log
In my case My disk was full 99%, It worked after I freed up to 80% of the disk.

How can i test my TSQL syntax?

Quick question: How do I get some kind of database to use to test my SQL syntax and create basic data.
I have Sqlite Code which I'll soon put on a server. I have SQL Server 2008 installed with visual studio 2010. I tried connecting to the database and had no luck.
I also tried using an .mdf file instead thinking it's a file and I won't have connectivity issues. Wrong, I still couldn't connect and I used this site to help me (i'm aware its 2005)
In that case I used:
var conn = new SqlConnection(#"Server=.\SQLExpress;AttachDbFilename=C:\dev\src\test\SQL_DB_VS_Test\test.mdf;Database=dbo;Trusted_Connection=Yes;");
exception
Unable to open the physical file "C:\dev\src\test\SQL_DB_VS_Test\test.mdf".
Operating system error 5: "5(Access is denied.)".
Cannot attach the file 'C:\dev\src\test\SQL_DB_VS_Test\test.mdf' as database 'dbo'.
With trusted = no I get Login failed for user ''. (What user am I suppose to set?). I created the .mdf with Visual Studio somehow.
What if you try this connection string:
var conn = new SqlConnection(#"Server=.\SQLExpress;
AttachDbFilename=C:\dev\src\test\SQL_DB_VS_Test\test.mdf;
Database=test;Integrated Security=SSPI;");
I don't think it's a good idea to call your database "dbo" (that's a SQL Server keyword - I wouldn't use it for my own purposes!), and also I believe you need to use Integrated Security=SSPI; to define Windows authentication - Trusted_Connection is not used for SQL Server connection strings, AFAIK.
Have you tried using SSMS to access your local instance? It's helpful for getting connected and getting everything setup. Also, I think the default install of Sql Express with VS only support trusted connections.
After creating the mdf file with visual studios right click the mdf and select properties. In it you'll see a row called Connection String. Copy/paste it into your app and it should connect. The key part is User Instance=True

sql exception when transferring project from usb to c:\

I'm working on a C# windows program with Visual Studio 2008. Usually, I work from school, directly on my usb drive. But when I copy the folder on my hard drive at home, an sql exception is unhandled whenever I try to write to the database. it is unhandled at the conn.Open(); line. here's the exception unhandled
Database 'L:\system\project\the_project\the_project\bin\Debug\PatientMonitoringDatabase.mdf' already exists. Choose a different database name. Cannot attach the file 'C:\Documents and Settings\Administrator\My Documents\system\project\the_project\the_project\bin\Debug\PatientMonitoringDatabase.mdf' as database 'PatientMonitoringDatabase'.
it's weird, because my connection string says |DataDirectory|, so it should work on any drive... here's my connection string:
string connStr = "Data Source=.\\SQLEXPRESS;AttachDbFilename=|DataDirectory|\\PatientMonitoringDatabase.mdf; " +
"Initial Catalog=PatientMonitoringDatabase; " +
"Integrated Security=True";
I think the complaint here is that your local SQL Server Express install already has a
PatientMonitoringDatabase attached and running.
Connect to localhost with SQL Server Management Studio Express (if not installed, download here) and remove/detach the existing PatientMonitoringDatabase database. Whether it's a persistent database or only active within a running application, you can't have 2 databases with the same name at the same time attached to a SQL Server instance.
The second exception you get because the SQL Server Express instance doesn't have permission to open the database file. What are the permissions on the file, and what is SQL Server running under?
problem solved. got lucky on that one. I got a hint by browsing microsoft forums. The hint led me to open my "SQL Server Configuration Manager", and I had to do something with "SQL Server (SQLEXPRESS)". So I double clicked on it, and changed the "Built-in Account" from "Network Service" to "Local System". and now it works.... I got lucky i guess...
but, you do have to detach the database. So for that, thx Nick Craver