C# creating a database programmatically with SMO

问题

I am trying to create a database, but once created, I cannot connect to it.

The server is Microsoft SQL Server 2008 and using .Net 4.5. We're creating the database with SMO, but we're usually using Dapper to connect and query the database.

This is the code I have so far, which works :

System.Data.SqlClient.SqlConnection con = new System.Data.SqlClient.SqlConnection(connectionString);

Microsoft.SqlServer.Management.Smo.Server srv = new Microsoft.SqlServer.Management.Smo.Server(new Microsoft.SqlServer.Management.Common.ServerConnection(con));

var database = new Microsoft.SqlServer.Management.Smo.Database(srv, dbName);

database.Create(false);

database.Roles["db_datareader"].AddMember(???);
database.Roles["db_datawriter"].AddMember(???);
database.Roles["db_backupoperator"].AddMember(???);

srv.Refresh();

Noce the ??? ? I have tried

System.Environment.UserDomainName + "\\" + System.Environment.UserName

and

System.Environment.UserName

but it fails (update) with the error Add member failed for DatabaseRole 'db_datareader'. with both values.

The problem is that when I create the database, I cannot coonect to it for some reason (using Dapper), from the same program. (update) I get the error message : Cannot open database \"<database_name>\" requested by the login. The login failed.\r\nLogin failed for user '<domain>\\<username>' (where <database_name> is the database name, <domain> my logon domain, and <username> my Windows logon).

Am I missing something? Am I doing th right thing? I've tried searching the web, but it seems no one creates database this way. The methods are there, it should work, no?

** Update **

If I comment the database.Roles["..."].AddMember(...) lines, and I add a break point at srv.Refresh(), resuming the program from there solves everything.

Why a break point solves everything? I can't just break the program in production... nor break the program when creating the database everytime.

回答1:

It sounds like the Dapper connection issue is a problem with SQL Server doing some of the SMO operations asynchronously. In all likelihood, the new Database is not ready for other users/connections immediately, but requires some small time for SQL Server to prepare it. In "human-time" (in SSMS, or a Breakpoint) this isn't noticeable, but "program-time" it too fast, so you probably need to give it a pause.

This may also be the problem with the Role's AddMember, but there a a number of things that could be wrong here, and we do not have enough information to tell. (specifically, does AddMember work later on? and are the strings being passed correct or not?)

回答2:

This is happening because you've created the user, but no login for that user. Though I don't know the exact syntax, you're going to have to create a Login. You'll want to set its LoginType to LoginType.WindowsUser. Further, you'll likely need to set the WindowsLoginAccessType to WindowsLoginAccessType.Grant and you'll need to set the Credential by building one, probably a NetworkCredential with the user name you want.

To put a visual on this, the Login is under the Security node for the Server in Management Studio whereas the User is under the Security node for the Database. Both need to exist for access to the SQL Server.

来源：https://stackoverflow.com/questions/17225391/c-sharp-creating-a-database-programmatically-with-smo

标签

sql-server-2008