As your contact data often comes from different sources, from time to time you may run into duplicate or possible duplicate entries. For example, if you import a contact into your database who has already subscribed to your newsletter through an online registration form with a different email address, you will have two profiles for the same person, who would consequently receive two copies of your next email campaign.
But you do not need to worry about duplicate contacts as the Emarsys Marketing Platform can manage most duplicates automatically. First, your account has a default duplicate handling method: it treats contacts having the same email address identical and merges them automatically. It runs this duplication check every time a new contact is about to be imported into your database via a registration form or manual entry.
When you use manual or automatic contact import in Emarsys, you can select the database fields against which duplication checks are run. These are called Unique Identifiers and can be defined after you have selected the import file you want to upload. The system will treat contacts as duplicates if all the fields marked as unique identifiers match those of an existing contact.
If you would like to change your unique identifier, please proceed as follows:
- Submit a ticket including your unique identifier change request to Emarsys Support.
- After estimating the costs of the requested changes, your Client Success Manager will contact you directly.
- Once the costs have been agreed between you and your Client Success Manager, the Emarsys Support Team will guide you through all the tasks that should be completed.
Managing duplicate suspects
And if there is a chance that two contacts are identical, for example, they have the same first and last name but a different email address, Emarsys may flag them as duplicate suspects. These suspect entries are listed on the Duplication Handling page in the Contacts menu, where you can merge them or mark them separate entries.
- Do not select single-choice fields as Unique Identifiers.
- If you check Do not send to duplicate email addresses option on the Email Settings page when setting up your campaign you can avoid sending more emails to the same recipient in an ad hoc batch campaign.
We strongly recommend that you enable the Do not send to duplicate email addresses option only for simple batch campaigns launched without any schedule. (When this option is enabled, there is no unschedule button on the Schedule page.)
Enabling this option in other scenarios, (A/B versions, test mails, Automation Center, Send Time Optimization, emails with case sensitive email addresses or email addresses having a space character at the end), can result in delivering emails to duplicate email addresses.
As a precaution, it is worth to convert all your email addresses to be imported to lowercase.
In terms of duplication handling, what happens to those text fields that differ in capitalization only (e.g. "Smith" and "smith")?
Contacts whose text field type unique identifiers differ in capitalization only are considered identical, and are merged automatically. Email address fields are still handled as case sensitive.