In this first installment of a two part series on duplicate detection in CRM 2011, we will look at duplicate detection settings and rules.  Let’s start with some basic information on duplicate detection.  CRM 2011 allows you to set policies and configure rules aimed at detecting duplicate records.  Based on the rules, users are alerted to potential duplicates.   Because duplicate data may have some value, CRM never automatically deletes any records from your system.  You or your users choose what to do with potential duplicates.

Duplicate detection must be enabled at the system level and on the entity.  Enabling duplicate detection and creating duplicate detection rules is typically done by the CRM system administrator.

Configure system duplicate detection settings:
To enable duplicate detection at the system level, you will navigate to Settings>Data Management>Duplicate Detection Settings.  Enable duplicate detection must be checked.

You may then select one or more of the three options when duplicate detection should occur:
• When a record is created or updated.   In this instance, users will be prompted before saving or creating a record when potential duplicates are identified based on the published duplicate detection rules.  Please note that duplicates are not detected when activating an inactive record, when merging two records, when activating a lead or when marking an activity as completed.
• When Microsoft Dynamics CRM for Outlook goes from offline to online.  If duplicates are detected during synchronization, the user is notified so that the duplicates may be resolved.
• During data import.  Each time a data import job is defined, the user has the choice to check for duplicates.

Once you have selected your desired options, click OK.

Duplicate Detection System Settings


To enable duplicate detection on an entity, navigate to Settings>Customization>Customizations>Customize the System>Entities and select the desired entity.  Scroll to the Data Management section of the General Tab and check the box next to Duplicate detection; click Save and then Publish.  By default, this option is checked for Accounts, Contacts and Leads.

Duplicate Detection Enabled on Entity


Edit or create duplicate detection rules
CRM 2011 includes default duplicate detection rules for Accounts, Contacts and Leads.  You may edit these rules based on your business needs and create additional rules as well.  To create or edit a duplicate detection rule, you will navigate to Settings>Data Management>Duplicate Detection Rules.
Edit an existing rule
When editing an existing rule, you may modify the criteria, change the case sensitive option or change the inactive records option.  You may not change the base record type or the matching record type.  To illustrate how to edit an existing rule, we will modify the Contacts with the Same Email Address rule to modify the criteria so that blank values are ignored.
1) Navigate to Settings>Data Management>Duplicate Detection Rules.
2) An existing rule must be unpublished before you may edit it; select the rule from the list, click on Unpublish and click OK when prompted.    Double click on the unpublished rule you wish to edit from the list to open it.
3) Check the Ignore Blank Values option for each criterion.
4) Click Save.
5) Click Publish and OK when prompted.  The updated rule will look like this:

Edit Duplicate Detection Rule


Before we move on to creating a new rule, here is a bit more about what happens when you publish a rule.  When a rule is published, a matchcode is created for every record in the matching record type for that rule.  When a new record is created or an existing record is updated, a matchcode is created which is compared to the matchcodes for existing records to identify potential duplicates based on the published rules.

Create a new rule
New duplicate detection rules may be created for out of the box entities and custom entities.   Duplicate detection criteria should be defined for fields that have unique values such as email address, account number or name.   To illustrate creating a duplicate detection rule, we will create a rule for Accounts based on the first seven characters of the first address line.
1) Navigate to Settings>Data Management>Duplicate Detection Rules
2) Click on New

New Rule


3) For Name, enter:  Accounts with same first 7 street 1
4) For Description, enter :  will be run manually for initial clean up by zip code, then may be scheduled to run once a day for all accounts
5) For Base record type select Account
6) Matching record type defaults to Account – leave it
7) Case Sensitive:   do not check
8) Exclude inactive matching records:  check
9) Under Field, select:  Address1 Street 1
10) Under Criteria, select:  Same first characters
11) Under No. of characters, enter:  7
12) Ignore blank values:  check
13) Click Save
14) Click Publish and OK when prompted.  The newly created rule looks like this:

The New Rule

In part two of the Duplicate Detection series, we will illustrate how check for duplicates on a list of records and how to create and schedule a duplicate detection jobs.  If you would like learn more about CRM 2011 duplicate detection, navigate to the Resource Center module in CRM and search on the term duplicate detection.