Started working after some days off, and generated a new dbml file through vs 2008. then it sent an error:
Object reference not set to an instance of an object.
MyBase.New(Global.System.Configuration.ConfigurationManager.ConnectionStrings("C__USERS_JIMMY_DOCUMENTS_VISUAL_STUDIO_2008_WEBSITES_LUNCHGUIDEN_APP_DATA_LUNCHGU"& _
row 88:"IDEN_MDFConnectionString").ConnectionString, mappingSource)
its like the dbml generates an own connection string, but i have done this alot of times before without it happening?
the problems is when i put it up on a sharp server.. it obviously cant find the connectionstring. what to do so the connectionstring doesnt get generated wrong?
Use the datacontext constructor with the connectionstring in parameter so it will not look after the default one
Ex:
using(MyDbContext context = new MyDbContext(ConfigurationManager.ConnectionStrings["myConnection"].ConnectionString))
{
...
}
Could it be that while you added a new entity to the model that the appSettings have been generated? It seems that linq to sql is always storing the connectionstring of the entity that was previously added to the model.
Related
Iam using couch-db version 2.2.0
and I want to make crud operations on couchdb database using .Net
so I installed Armchair.Core Nuget Package version 0.11.2
and in order to add d a new document I, followed the code that is mentioned in
not finished wiki yet
https://bitbucket.org/dboneslabs/arm-chair/wiki/main-api/session-api.md
Database mydatabase = new Database("TestDb",newConnection("http://localhost:5984"));
using (var session = mydatabase.CreateSession())
{
var author = new Person("Jone");
session.Add(author);// NOTE: If no Id has been assigned before the instance is added to the Session, then ArmChair will assign it. After the object is committed to the database, the revision will then be set onto the instance
session.Commit();
}
but I still getting the error
Object reference not set to an instance of an object.
also mydatabase variable mentioned in previous code has values null for Connection and DataBase Parameters even though i passed them in the constructor as it doesn't connect to couchdb database at all and never tries to create database TestDb
any help please ,are there any wrong calls in my code
ArmChair connects to an existing database and does not create one.
if you want to create a database, have a look a look at the sample application, in the Autofac registration there is a method which ensures that there is a database created.
https://bitbucket.org/dboneslabs/arm-chair/src/bd4e70d6c51d8b45cfb89eb65ecf81a4ecefb691/samples/todo/Todo.Service/Infrastructure/Modules/DataAccessModule.cs#lines-62
its not the pretty-est of code but works.
Simply trying to find out the correct syntax for my connection string. Before anyone asks, yes I did look at other SO answers, and no they did not work for me. Here a couple of attempts I made from looking at other SO questions like the one I am asking
Server=(local);Database=SalesOrdersExample;Integrated Security= true
Data Source=(local);Database=SalesOrdersExample;Integrated Security=SSPI
Server=.\\SQLEXPRESS;Database=SalesOrdersExampleDataSet;Integrated Security=true
None of them worked (I have a Console.WriteLine("test"); thrown in there and it works up until I try conn.Open() (opening the connection to database) so I'm assuming that it must be my connection string since nothing gets written after conn.Open())
Console.WriteLine("test"); // works
SqlConnection conn = new SqlConnection("Server=.\\SQLEXPRESS;Database=SalesOrdersExampleDataSet;Integrated Security=true");
Console.WriteLine("test"); // works
conn.Open();
Console.WriteLine("test"); // does not work
So some information about the database is that it's local under my 'Data Connections' in my Server Explorer. I also have the .xsd file in my project so I have linked the Data Set to the current project I am on. Here is a picture representation to confirm that I have both the Data Connection and the Data Set.
EDIT: SO does not allow me to post pictures until I have 10 rep so here is direct link to picture:
DB Screenshot
Any help is appreciated thank you.
Visual Studio comes with LocalDB database, which is not exactly SQL Server Express database.
Try something like this:
Server=(localdb)\v11.0;Integrated Security=true;
or
Data Source=(LocalDB)\v11.0; AttachDbFileName=|DataDirectory|\DatabaseFileName.mdf; InitialCatalog=DatabaseName;Integrated Security=True;MultipleActiveResultSets=True
If using in c# code, you can use # to avoid problems with backslash characters:
SqlConnection conn =
new SqlConnection(#"Server=(localdb)\v11.0;Integrated Security=true;");
I am building the sample MvcMovie tutorial for ASP.NET MVC 4. I'm using EntityFramework Code First features and created a connectionString as follows.
<add name="MoveDBContext"
connectionString="Data Source=(LocalDB)\v11.0;AttachDbFilename=|DataDictionary|\Movies2.mdf;Integrated Security=True"
providerName="System.Data.SqlClient"
/>
Everything worked fine at this point. But then I realized that I named my connection string MoveDBContext instead of MovieDBContext and, being the perfectionist I renamed it. After doing this I now receive an error in my MoviesController/Index method.
public class MoviesController : Controller
{
private MovieDBContext db = new MovieDBContext();
public ActionResult Index()
{
return View(db.Movies.ToList()); // Error: Invalid value for key 'attachdbfilename'
}
...
}
If I change the name back to MoveDBContext the error goes away.
Can anyone tell me where this original name is being referenced?
EF, by default, looks for a connection string with the same name as the type that extends DbContext.
Or, better put by Scott:
By default, when you create a DbContext class with EF code-first, it
will look for a connection-string that matches the name of the
context-class. Since we named our context class “NerdDinners”, it
will by default look for and use the above “NerdDinners” database
connection-string when it is instantiated within our ASP.NET
application.
Edit:
After looking closer, I think your connection string is the problem. You've got DataDictionary instead of DataDirectory. Try this (line feeds added for readability):
<add name="MovieDBContext"
connectionString="Data Source=(LocalDB)\v11.0;
AttachDbFilename=|DataDirectory|\Movies.mdf;
Integrated Security=True"
providerName="System.Data.SqlClient" />
Apparently, as Ken said, the MoveDBContext was not being referenced.
I removed the entire connectionString from the web.config and everything still functioned correctly.
So, it still begs the question, "How did Visual Studio know to create a database in my SQLExpress instance?" and "Where is that configured at?"
I have about 85 SSIS packages that are using the same connection manager.
I understand that each package has its own connection manager.
I am trying to decide what would be the best configurations approach to simply set the connectionstring of the connection manager based on the server the packages are residing on.
I have visited all kinds of suggestions online, but cannot find anywhere the practice where I can simply copy the configuration from one package to the rest of the packages.
There are obviously many approaches such as XML file, SQL Server, Environment Variable, etc.
All the articles out there are pointing to use an Indirect method by using XML or SQL approach. Why would using an environment variable for just holding a connection string is such a bad approach?
Any suggestions are highly appreciated.
Thanks!
Why would using an environment variable for just holding a connection string is such a bad approach?
I find the environment variable or registry key configuration approach to be severely limited by the fact that it can only configure one item at a time. For a connection string, you'd need to define an environment variable for each catalog on a given server. Maybe it's only 2 or 3 and that's manageable. We had a good 30+ per database instance and we had multi-instanced machines so you can see how quickly this problem explodes into a maintenance nightmare. Contrast that with a table or xml based approach which can hold multiple configuration items for a given configuration key.
...best configurations approach to simply set the connectionstring of the connection manager based on the server the packages are residing on.
If you go this route, I'd propose creating a variable, ConnectionString and using it to configure the property. It's an extra step but again I find it's easier to debug a complex expression on a variable versus a complex expression on a property. With a variable, you can always pop a breakpoint on the package and look at the locals window to see the current value.
After creating a variable named ConnectionString, I right click on it, select Properties and set EvaluateAsExpression equal to True and the Expression property to something like "Data Source="+ #[System::MachineName] +"\\DEV2012;Initial Catalog=FOO;Provider=SQLNCLI11.1;Integrated Security=SSPI;"
When that is evaluated, it'd fill in the current machine's name (DEVSQLA) and I'd have a valid OLE DB connection string that connects to a named instance DEV2012.
Data Source=DEVSQLA\DEV2012;Initial Catalog=FOO;Provider=SQLNCLI11.1;Integrated Security=SSPI;
If you have more complex configuration needs than just the one variable, then I could see you using this to configure a connection manager to a sql table that holds the full repository of all the configuration keys and values.
...cannot find anywhere the practice where I can simply copy the configuration from one package to the rest of the packages
I'd go about modifying all 80something packages through a programmatic route. We received a passel of packages from a third party and they had not followed our procedures for configuration and logging. The code wasn't terribly hard and if you describe exactly the types of changes you'd make to solve your need, I'd be happy to toss some code onto this answer. It could be as simple as the following. After calling the function, it will modify a package by adding a sql server configuration on the SSISDB ole connection manager to a table called dbo.sysdtsconfig for a filter named Default.2008.Sales.
string currentPackage = #"C:\Src\Package1.dtsx"
public static void CleanUpPackages(string currentPackage)
{
p = new Package();
p.app.LoadPackage(currentPackage, null);
Configuration c = null;
// Apply configuration Default.2008.Sales
// ConfigurationString => "SSISDB";"[dbo].[sysdtsconfig]";"Default.2008.Sales"
// Name => MyConfiguration
c = p.Configurations.Add();
c.Name = "SalesConfiguration";
c.ConfigurationType = DTSConfigurationType.SqlServer;
c.ConfigurationString = #"""SSISDB"";""[dbo].[sysdtsconfig]"";""Default.2008.Sales""";
app.SaveToXml(sourcePackage, p, null);
}
Adding a variable in to the packages would not take much more code. Inside the cleanup proc, add code like this to add a new variable into your package that has an expression like the above.
string variableName = string.Empty;
bool readOnly = false;
string nameSpace = "User";
string variableValue = string.Empty;
string literalExpression = string.Empty;
variableName = "ConnectionString";
literalExpression = #"""Data Source=""+ #[System::MachineName] +""\\DEV2012;Initial Catalog=FOO;Provider=SQLNCLI11.1;Integrated Security=SSPI;""";
p.Variables.Add(variableName, readOnly, nameSpace, variableValue);
p.Variables[variableName].EvaluateAsExpression = true;
p.Variables[variableName].Expression = literalExpression;
Let me know if I missed anything or you'd like clarification on any points.
I have a simple find delete case:
var query = CompanyUsers
.Where ( cu => cu.eMail.Contains( "123#email.com") || cu.eMail.Contains( "456#email.com"))
ServicesEntities se = new ServicesEntities();
se.DeleteObject( query );
ServiceEntities is a EntityFramework 4.1 DLL. The only thing in the DLL is the EF model.
When I try to delete I get:
"ArgumentException: The specified named connection is either not found in the configuration, not intended to be used with the EntityClient provider, or not valid."
If I try adding the name of the connection string in the app.config file like this:
ServicesEntities se = new ServicesEntities("ServicesEntities");
I get: ArgumentException: Format of the initialization string does not conform to specification starting at index 0.
How can I use my EF model and perform deletes using the conext. Is it possible to pass through the connection string that LINQPad appears to be creating in the properties tab or at the minimum use the one from the app.config?