The xDB Contact

What is a contact?

All visitors are stored in the xDB - including anonymous visitors. As soon as you identify yourself by providing Sitecore with an e-mail address, you become a contact.

You can view identified contacts and individual visitors in the Experience Profile interface. Note that this interface does not necessarily pull all of its content directly from MongoDB.

Where are contacts stored?

The raw contact data is stored in the contacts collection of the analytics MongoDB. MongoDB stores information in JSON format. Here is a contact that has provided a first name, surname, and e-mail address:

{
    "_id" : LUUID("ad72f93a-a071-1f40-ac68-c165faf21e91"),
    "Identifiers" : {
        "IdentificationLevel" : 2,
        "Identifier" : "extranet\\jill_at_mail_dot_com"
    },
    "Lease" : {
        "ExpirationTime" : ISODate("2015-02-06T11:32:21.381Z"),
        "Owner" : {
            "Type" : 0
        }
    },
    "System" : {
        "Classification" : 0,
        "OverrideClassification" : 0,
        "VisitCount" : 1,
        "Value" : 0
    },
    "Personal" : {
        "FirstName" : "Jill",
        "Surname" : "Bean"
    },
    "Emails" : {
        "Preferred" : "work_email",
        "Entries" : {
            "work_email" : {
                "SmtpAddress" : "jillsmtp@mail.com"
            }
        }
    }
}

A bare bones contact that didn’t do much on the site looks like this - they did not submit any information for us to use to identify them:

{
    "_id" : LUUID("96ef68cb-644a-8b43-a5e9-8567f7dc63bb"),
    "System" : {
        "Classification" : 0,
        "OverrideClassification" : 0,
        "VisitCount" : 1,
        "Value" : 0
    },
    "Lease" : null
}

Contact data is also aggregated down to the reporting database (which is used primarily by the reporting API and Engagement Analytics) and the analytics index, which is used by the Experience Profile search page and Email Experience Manager.

What is the difference between a contact and a user?

When we talk about users in Sitecore, we tend to mean ASP.NET membership users. There is no direct link between a contact and a user in the xDB - you can be a contact without being a registered user. However, the xDB does store identifiers that you can use to link your contact to an ASP.NET user in code. The contact below is ‘known’ and identified by their Sitecore extranet user:

"Identifiers" : {
	        "IdentificationLevel" : 2,
	        "Identifier" : "extranet\\jill_at_mail_dot_com"
	    }

As can be seen from the ContactIdentificationLevel enum below, 2 denotes known.

  public enum ContactIdentificationLevel
  {
	    None = 0,
	    Anonymous = 1,
	    Known = 2,
  }

Even though there is an option for ‘Anonymous’, you will find that the Identifiers section is simply missing from anonymous contacts.

Identifying a contact in code

Web Forms for Marketers will automatically ‘identify’ a contact to match a registered user if you use any of its ‘log in’ Save Actions. To identify a contact yourself, do the following:

var domainUser = "extranet\\jill_at_mail_dot_com";
Tracker.Current.Session.Identify(domainUser);

Remember to format the username correctly, including domain and double backslash. The xDB will now associate your logged-in visitor with an existing xDB record, provided this is not their first visit.

Automatic merge

Example of actions that lead to the automatic merge of contact data:

• User opens fresh and clean browser session and performs some actions.

• His session is ended or data are flushed in another way to xDB. It leads to creation of anonymous contact in db.Contacts. This is how anonymous contact looks like in xDB:

    {
        "_id" : NUUID("9deb81b7-4a1c-4093-9a8f-7d79484549d9"),
        "System" : {
            "Classification" : 0,
            "OverrideClassification" : 0,
            "VisitCount" : 1,
            "Value" : 0
        },
        "Lease" : null
    } Notice, that there are no Identifier.
  

• In the same browser User get’s identified as already existing contact at some point. For example, he fills the form that identifies him as one of the existing contacts.

It leads to the situation, where newly created anonymous contact cannot be deleted, because it already has interactions and probably other data, associated with it. Therefore merging of anonymous and already existing contact happens. All data saved in anonymous contact, like Visit count and Value gets transferred to old existing contact, and anonymous contact loses all fields except of _id, but also gets Successor field, which stores an id of old existing contact.

This is what our anonymous contact becomes after merging:

    {
        "_id" : NUUID("9deb81b7-4a1c-4093-9a8f-7d79484549d9"),
        "Successor" : NUUID("dbfb1cac-861f-4e62-9007-834dd93e589f")
    }

Old contact has id "dbfb1cac-861f-4e62-9007-834dd93e589f".

This merging allows to create a link between old and new contact and do not lose any interaction data.

Extending a Contact

There are a number of ways to add more information to a contact.

• Use facets for permanent, business-critical information - such as ‘Loyalty Card Number’
• Use extensions for more ad-hoc information - such as ‘Favourite Vacation Memory’
• Use tags for ad-hoc information that needs to be tracked over time