Change MSSQL Schema Ownership via Powershell - sql-server

Question

I'm trying to change the "schemas owned by this user" on a database using the following powershell script:
$dbname = "mydb"
$sql_server = "mysqlserver"
$username = "myuser"
[System.Reflection.Assembly]::LoadWithPartialName("Microsoft.SqlServer.SMO") | Out-Null
$server = New-Object ("Microsoft.SqlServer.Management.Smo.Server")($sql_server)
$db = $server.Databases["$dbname"]
$login = $server.Logins[$username]
$roleName = "db_owner"
if(-not $db.Users.Contains($login.Name)){
$user = New-Object('Microsoft.SqlServer.Management.Smo.User') $db, $login.Name
$user.Login = $login.Name
$user.create();
}
$user = $db.Users[$login.Name]
$role = $db.Roles[$roleName]
$role.AddMember($user.Name);
$schema = $db.Schemas["dbo"]
$schema.Owner = "myuser"
$schema.Alter()
When I get to the step $schema.Alter() I get the following error:
Exception calling "Alter" with "0" argument(s): "Alter failed for Schema 'dbo'. "
At line:1 char:1
+ $schema.Alter()
+ ~~~~~~~~~~~~~~~
+ CategoryInfo : NotSpecified: (:) [], MethodInvocationException
+ FullyQualifiedErrorId : FailedOperationException
I get the impression the Alter Method is looking for more parameters but I'm not sure what parameters it wants. Anyone have any suggestions what I'm doing wrong?
Thanks
Brad

Answer 1

In my experience, the top level exception is not helpful. My typical method for dealing with this is something like $e = $error[0]; and then calling $e.Exception, $e.Exception.InnerException, $e.Exception.InnerException.InnerException, … until I get to the actual error. This doesn't solve your problem, but at least can give you a better idea of what the problem is.