We are migrating a project from .NET Framework to .NET Core, the project is working with multiple data bases that are on the same SQL server. In the past we used a transaction scope for any transaction that we wanted to roll back in case of an error.
When the transaction is involving multiple DBs the transaction is being promoted to a distributed transactions which is not supported in .NET Core.
Question is, if all DBs are actually on the same server, if I will use a 'cross-database queries' like is suggested at the very last part of this Answer will I be insured against such a scenario?
Does 'cross-database queries' simply means running raw-SQL commands like:
using(TransactionScope scope = new TransactionScope())
{
var connection = new SqlConnection(connectionString);
connection.Open();
var SqlComm1 = new SqlCommand("Insert into TableA...", connection);
SqlComm1 .ExecuteNonQuery();
var SqlComm2 = new SqlCommand("Insert into [DB2].[dbo].[TableB]...";
SqlComm2 .ExecuteNonQuery();
.
.
}
if not, can I get a code example of what it actually is?
lastly, while using 'cross-database queries' can I take advantage of anything from my actual DBContexts? like connections, dbSets or anything and if so, how?
I have a PowerBuilder.net console application that uses SQLNCLI10 to connect a SQL Server 2008 R2. This applications needs to be executed from a ASP.NET MVC website hosted in the same server, and its output readed.
This is the code for executing the application on the MVC:
var proc = new System.Diagnostics.Process
{
StartInfo = new System.Diagnostics.ProcessStartInfo
{
FileName = ConfigurationManager.AppSettings["PB_EXE"],
Arguments = Credentials.ClientId + " " + reference,
UseShellExecute = false,
RedirectStandardOutput = true,
WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden
}
};
When the application is executed from the MVC, the PBTransaction objects returns the generic "Transaction not connected" sql error.
The thing is, the application runs well with a .bat that call the executable with parameters. Even more, a simple WinForms using the same code above, gets the transaction connected successfully.
I have alredy tried setting the ApplicationPool of the website to the administrator of the server, with the same results.
What I'd check first to solve connectivity issues on a PB.NET console application.
Putting some logging into the console application and examine the Transaction object immediately before and after attempting the connection. It will likely provide necessary information to identify the culprit.
Make sure PowerBuilder database connectivity run-time libraries (e.g. PBORA010.DLL) are installed on the server and accessible to the role running the application.
If the connection uses ODBC/JDBC make sure any DSNs needed on server are accessible to the console application.
I'm using SQL Server and ASP.NET. I have the following function:
Using js = daoFactory.CreateJoinScope()
Using tran = New Transactions.TransactionScope()
'...
tran.Complete()
End Using
End Using
However, the following exception is thrown:
The transaction manager has disabled its support for remote/network transactions.
Description of JoinScope:
Public Class JoinScope
Implements IJoinScope
Implements IDisposable
'...
End Class
I have worked this way in another application with the same environment without a problem, but here I have this problem. What could I do to fix the issue?
Make sure that the "Distributed Transaction Coordinator" Service is
running on both database and client.
Also make sure you check "Network DTC Access", "Allow Remote Client",
"Allow Inbound/Outbound" and "Enable TIP".
To enable Network DTC Access for MS DTC transactions
Open the Component Services snap-in.
To open Component Services, click Start. In the search box, type dcomcnfg, and then press ENTER.
Expand the console tree to locate the DTC (for example, Local DTC) for which you want to enable Network MS DTC Access.
On the Action menu, click Properties.
Click the Security tab and make the following changes:
In Security Settings, select the Network DTC Access check box.
In Transaction Manager Communication, select the Allow Inbound and Allow Outbound check boxes.
I had a store procedure that call another store Procedure in "linked server".when I execute it in ssms it was ok,but when I call it in application(By Entity Framework),I got this error.
This article helped me and I used this script:
EXEC sp_serveroption #server = 'LinkedServer IP or Name',#optname = 'remote proc transaction promotion', #optvalue = 'false' ;
for more detail look at this:
Linked server : The partner transaction manager has disabled its support for remote/network transactions
In my scenario, the exception was being thrown because I was trying to create a new connection instance within a TransactionScope on an already existing connection:
Example:
void someFunction()
{
using (var db = new DBContext(GetConnectionString()))
{
using (var transaction = new TransactionScope(TransactionScopeOption.Required, new TransactionOptions { IsolationLevel = System.Transactions.IsolationLevel.ReadUncommitted }))
{
someOtherFunction(); // This function opens a new connection within this transaction, causing the exception.
}
}
}
void someOtherFunction()
{
using (var db = new DBContext(GetConnectionString()))
{
db.Whatever // <- Exception.
}
}
I was getting this issue intermittently, I had followed the instructions here and very similar ones elsewhere. All was configured correctly.
This page: http://sysadminwebsite.wordpress.com/2012/05/29/9/ helped me find the problem.
Basically I had duplicate CID's for the MSDTC across both servers. HKEY_CLASSES_ROOT\CID
See: http://msdn.microsoft.com/en-us/library/aa561924.aspx section Ensure that MSDTC is assigned a unique CID value
I am working with virtual servers and our server team likes to use the same image for every server. It's a simple fix and we didn't need a restart. But the DTC service did need setting to Automatic startup and did need to be started after the re-install.
Comment from answer: "make sure you use the same open connection for all the database calls inside the transaction. – Magnus"
Our users are stored in a separate db from the data I was working with in the transactions. Opening the db connection to get the user was causing this error for me. Moving the other db connection and user lookup outside of the transaction scope fixed the error.
I post the below solution here because after some searching this is where I landed, so other may too. I was trying to use EF 6 to call a stored procedure, but had a similar error because the stored procedure had a linked server being utilized.
The operation could not be performed because OLE DB provider _ for linked server _ was unable to begin a distributed transaction
The partner transaction manager has disabled its support for remote/network transactions*
Jumping over to SQL Client did fix my issue, which also confirmed for me that it was an EF thing.
EF model generated method based attempt:
db.SomeStoredProcedure();
ExecuteSqlCommand based attempt:
db.Database.ExecuteSqlCommand("exec [SomeDB].[dbo].[SomeStoredProcedure]");
With:
var connectionString = db.Database.Connection.ConnectionString;
var connection = new System.Data.SqlClient.SqlConnection(connectionString);
var cmd = connection.CreateCommand();
cmd.CommandText = "exec [SomeDB].[dbo].[SomeStoredProcedure]";
connection.Open();
var result = cmd.ExecuteNonQuery();
That code can be shortened, but I think that version is slightly more convenient for debugging and stepping through.
I don't believe that Sql Client is necessarily a preferred choice, but I felt this was at least worth sharing if anyone else having similar problems gets landed here by google.
The above Code is C#, but the concept of trying to switch over to Sql Client still applies. At the very least it will be diagnostic to attempt to do so.
I was having this issue with a linked server in SSMS while trying to create a stored procedure.
On the linked server, I changed the server option "Enable Promotion on Distributed Transaction" to False.
Screenshot of Server Options
If you could not find Local DTC in the component services try to run this PowerShell script first:
$DTCSettings = #(
"NetworkDtcAccess", # Network DTC Access
"NetworkDtcAccessClients", # Allow Remote Clients ( Client and Administration)
"NetworkDtcAccessAdmin", # Allow Remote Administration ( Client and Administration)
"NetworkDtcAccessTransactions", # (Transaction Manager Communication )
"NetworkDtcAccessInbound", # Allow Inbound (Transaction Manager Communication )
"NetworkDtcAccessOutbound" , # Allow Outbound (Transaction Manager Communication )
"XaTransactions", # Enable XA Transactions
"LuTransactions" # Enable SNA LU 6.2 Transactions
)
foreach($setting in $DTCSettings)
{
Set-ItemProperty -Path HKLM:\Software\Microsoft\MSDTC\Security -Name $setting -Value 1
}
Restart-Service msdtc
And it appears!
Source: The partner transaction manager has disabled its support for remote/network transactions
In case others have the same issue:
I had a similar error happening. turned out I was wrapping several SQL statements in a transactions, where one of them executed on a linked server (Merge statement in an EXEC(...) AT Server statement). I resolved the issue by opening a separate connection to the linked server, encapsulating that statement in a try...catch then abort the transaction on the original connection in case the catch is tripped.
I had the same error message. For me changing pooling=False to ;pooling=true;Max Pool Size=200 in the connection string fixed the problem.
I'm creating a web service which has a number of methods, all of which make use of a SqlConnection. It seems logical that I would declare a class level connection and initialise it in the web service constructor.
Problem is I cannot find a definitive way to release the connection when the web service call completes, so I have a connection leak. I've tried overriding the Dipose() method but it doesn't get called in a reasonable timeframe (actually not at all in my testing). For good measure I also tried attaching a handler to the Disposed() event but as expected same problem.
Is there nothing similar to Page.OnUnload for web service classes? It seems hard to believe I would have to establish a separate connection in every individual method.
Any suggestions?
It seems logical that I would declare a class level connection and initialise it in the web service constructor.
No, this doesn't seem logical at all. ADO.NET uses a connection pooling so that you don't need to do this. This connection pool is per connection string per application domain.
So you could simply draw a new connection from the pool in each web method and return it to the pool at the end (the using statements will take care of this):
[WebMethod]
public void Foo()
{
// Here you are NOT creating a new connection to the database
// you are just drawing one from the connection pool
using (var conn = new SqlConnection(SomeConnectionString))
using (var cmd = conn.CreateCommand())
{
// Here you are NOT opening a new connection to the database
conn.Open();
cmd.CommandText = "SELECT id FROM foo";
using (var reader = cmd.ExecuteReader())
{
while (reader.Read())
{
// do something with the results
}
}
} // Here you are NOT closing the connection, you are just returning it to the pool
}
So here's an advice: don't try to manage connections manually by using some class fields, static fields, ... Leave this management to ADO.NET as it does it better.
Remark: The code I've shown usually resides in a data access layer which is called by the web method.
I am looking to port my very basic DBMS software from classic ASP to ASP.net - however the user would need to input the connection details in order to connect to their specific DBMS server.
Is this at all possible with ASP.NET MVC (very similar to DSN-less connections in ASP).
Cheers,
Joel
The question should really be "is this possible with .NET", ASP.NET MVC is not a database technology, and DSN-less connections aren't ASP technology either. In .NET, it is the ADO.NET framework that allows you to access database resources, and it can be used from any .NET code, be it desktop, web and mobile too.
There are some specialised libraries for certain platforms, .NET includes native support for Sql Server, you can get the MySql Connector for .NET, etc.
All of these providers are built around the ADO.NET provider model, you can either use them explicitly, or you can use the provider-agnostic method. Here are two examples, the first being Sql Server:
string connectionString = "Server=....";
using (SqlConnection connection = new SqlConnection(connectionString))
{
using (SqlCommand command = new SqlCommand("SELECT [Name] FROM [People]"))
{
connection.Open();
using (SqlDataReader reader = command.ExecuteReader())
{
// Do something here.
}
}
}
In the above example, I'm using the specific Sql Server ADO.NET types to create a connection to a database and execute an arbitrary query against it.
If you are intended to support multiple database platforms, it's probably best to design your code such that it can utilise the ADO.NET Factory classes which are specialised factories geared to the creation of platform specific types. In the example below, I've used the Factory classes to access a MySql Server database:
string connectionString = "Server=....";
DbProviderFactory factory = DbProviderFactories.GetFactory("MySql.Data");
using (DbConnection connection = factory.CreateConnection())
{
connection.ConnectionString = connectionString;
using (DbCommand command = factory.CreateCommand())
{
command.CommandText = "SELECT `Name` FROM Page";
connection.Open();
using (DbDataReader reader = command.ExecuteReader())
{
// Do something here.
}
}
}
Not the perfect example, but enough to get you going, but it's important to remember that DSN-less connections are not tied to ASP or ASP.NET.
Hope that helps.