Question

I’m missing a concept here. I was assuming that Membership.DeleteUser() would expunge a user from my membership tables. My code:

// remove all but 'admin' from Membership
MembershipUserCollection users = Membership.GetAllUsers();

foreach ( MembershipUser user in users )
{
    if ( user.UserName != "admin" )
    {
        Membership.DeleteUser( user.UserName );
    }
}

DeleteUser() fails with exception:

The DELETE statement conflicted with the REFERENCE constraint 
"FK__aspnet_Me__UserI__58D1301D". The conflict occurred in database 
"MyDatabase", table "dbo.aspnet_Membership", column 'UserId'.
The statement has been terminated.

In my Web.config:

<membership defaultProvider="MyMembershipProvider">
  <providers>
    <clear/>
    <add name="MyMembershipProvider" type="System.Web.Security.SqlMembershipProvider" connectionStringName="MembershipConnectionString" enablePasswordRetrieval="false" enablePasswordReset="true" requiresQuestionAndAnswer="false" requiresUniqueEmail="false" maxInvalidPasswordAttempts="5" minRequiredPasswordLength="5" minRequiredNonalphanumericCharacters="0" passwordAttemptWindow="10" applicationName="MyApplication"/>
  </providers>
</membership>

I get it that there’s a foreign key relationship between Membership.UserId -> Users.UserId but would have assumed that the whole point of DeleteUser() is to remove all the records for this user in the Membership, User and UsersInRoles tables, to name a few.

Of course, I could go straight into the Membership table and delete the appropriate record, but that’s defeating the purpose of using the API. What am I doing wrong? What is the correct way to delete a user from the Membership tables?

Answer 1

Well, Membership.DeleteUser(string) calls SqlMembershipProvider.DeleteUser(string, bool) with true, and that calls the stored proc aspnet_Users_DeleteUser. That sproc has code in it to delete the various extra data in other tables that are related.

You can check your sproc to see if it’s been altered.

The only other thing I can think of is whether or not you created any other foreign key relationships to the Membership tables, such as to your own users table? If so, you would have to delete those records first. This is one reason it’s not recommended to create such foreign key relationships.

Check the FK relationships on the aspnet_Membership table and see if there are any that shouldn’t be there.