When you work with a large volume of data, it gets quite challenging to keep your database free from duplicates. As the avenues to create records in CRM increase, the chances of duplicates to get generated increase as well. For example, the same lead may get created via import as well as, say, APIs. To help you manage a clean set of data, Zoho CRM offers both proactive and reactive solutions.

• Arrest duplicates before they can be created
  By marking a certain field as a "unique field", you can stop the creation of a duplicate record. This is a proactive way to maintain a clean database. For example, if you have marked the Phone number field as a unique field in the Leads module, CRM will alert you if you create a second lead with the same phone number as an existing lead.
  See also: Unique fields
• Merge duplicate records
  Despite creating unique fields and double checking data, if you still think there could be duplicate records in your CRM, you can use Zoho CRM's de-duplication tools to merge them. They are as follows:
  • Find & Merge Duplicate Records
  • De-duplicate Records (Auto-merge duplicates)
    • Resolving conflict in de-duplication

Find & Merge Duplicate Records	De-duplicate Records
When to use: It is ideal to use this feature if you are specifically looking for a particular record's duplicates. Example: You know that a lead called "David Smith" has been duplicated and you wish to find and merge those leads.	When to use: It is ideal to use this feature when you are not clear if there are duplicates and you want CRM to run a duplication check based on certain unique fields. Example: You run a duplication check on the Leads module based on the Email field.
How it works: Go to the specific record's Detail page and click the Find & Merge Duplicates option. This will fetch the duplicate entries for that record.	How it works: You need not go to a specific record's page. Simply click the De-duplicate tool from the module's list view and select the fields based on which the search must be made. Example: If you choose the Email and Company fields, CRM will search for all records in which the Email and Company field values are the same. You can run a check based on a maximum of 3 fields at a time.
Once the list of duplicate records has been displayed, you can manually select and merge the records from the search results. CRM does not automatically merge the duplicates You can merge a maximum of 3 fields at a time.	CRM automatically merges duplicate entries if they are exact copies of each other. In case of conflict*, you must manually resolve the conflict to instruct CRM on which records should be taken as the master record and merge them. (*)Conflict Example: Assume there are two leads with the same names, company, but with different phone numbers. In this case, there the problem of conflicting phone numbers must be resolved manually. If there are no such conflicts and all fields match, CRM merges the records automatically.

Find & Merge Duplicate Records

If you are looking to merge the duplicate entries of specific records, Find & Merge Duplicates is the ideal tool for you. Simply go to the Detail page of the specific record and deploy this tool to fetch its duplicates.

The Find & Merge Duplicates tool also allows you to enter further criteria to search for duplicates. There are 6 fields in which you can specify the criteria in each module. Once the duplicates have been found, you can merge them manually.

Note that this tool is available only in the Leads, Accounts, Contacts and Vendors modules and you can merge a maximum of 3 records at a time.

Availability

To find and merge duplicate records

1. Click the Leads, Accounts, Contacts or Vendors tab.
2. In the [Module] Home page, click the required record.
   (Module refers to the tabs.)
3. In the [Module] Details page, click the Moreicon > Find & Merge Duplicates.
   Available only in the Leads, Accounts, Contacts and Vendors modules
4. In the Find and Merge Duplicate for [records]page, do the following:
   • In the Search Criteria section, the matching criteria are displayed.
   • Specify additional criteria if required, and then click Search.
     
   • In the Matching Records section, select at least two records to be merged.
   • Click Next.
     
     
5. In the Merge [records] page, select the record that you want to maintain as the Master Record.
   You can click SELECT ALL, if you wish to take all the master record values as final and merge the duplicates.
   
   If not, click the radio buttons near the corresponding fields of other records to instruct CRM on which field values should be considered "final" in order to merge duplicates.
   The values thus selected appear under the MASTER RECORD column. You can merge a maximum of 3 records at a time.
    
6. Click Merge.

De-duplicate records (Auto-merge duplicates)

In case you are not sure of the records that have been duplicated, you can let CRM run a check on modules using the De-duplicate tool. CRM will automatically find and merge exact matches. In case of conflicts in field values, you must manually resolve the conflicts and merge records.

Consider the following image. There are three exact matches and there are two records in which the just phone number field differs. In this case, CRM will auto-merge the first three records and prompt the user to resolve conflict in the last two records. Once the conflict has been resolved, the records will be merged.

Availability

To merge duplicate records using the De-duplicate tool

1. Click the Leads, Accounts, Contacts or Vendors tab.
2. In the [Module] Home page, under [Module] Tools, click Deduplicate [Module].
   (Module refers to the tabs like Leads, Contacts, etc.)
   
3. In the Deduplicate [Records] page, click the fields by which you would like to search the duplicate records.
   
   You can select up to 3 fields. CRM will search for duplicates based on these fields.
   For example, if you select Email and Company, CRM will look for records in which the Email ID and Phone fields are the same.
   Note that fields that you have marked as unique appear here. If you have not marked unique fields, CRM will display a standard set of unique fields for the module.
4. Click Find and Merge Duplicates.
   A popup window informing you of the de-duplicate function appears. Click OK.
   
   If the duplicates found by CRM are exact copies of each other, CRM will automatically merge them. In that case, this requires no further action from the user.
   Note that in the case of auto-merge, the record with latest "Last Activity Time" will be considered as the master record.
   In case there is a conflict in some of the field values between the duplicates, then you must resolve the conflict and then manually merge the records.
    

Resolve conflicts in de-duplication

A conflict in de-duplication refers to a case where the field values within duplicates are different. For example, there are two records called David Smith, where all field values except the phone number are the same. In this case, CRM does not know which record to consider as the final and merge them. This is an example of a conflict and this must be resolved by the user. There are two ways to resolve conflict in de-duplication.

• Resolve immediately - When CRM throws a popup on the conflict, you can immediately resolve it by click Resolve Now.
• Resolve later - If you are busy with other activities, click Resolve Later. You will be sent an email notification on the de-duplication details. Access the link to resolve conflict from this email. Note that this link will be valid only for three days.

Once you click to resolve conflict, you will be taken to the Deduplicate [Records] page, where the particular record and the number of duplicate entries found are displayed. Click View.
(You can switch between the tabs to view the duplicates under each selected field.) 

1. As per the example above, there are two leads with the same field values except for the phone number. So in the Deduplicate Leads page, you can see that the records are listed as columns.
2. Select a Master Record. You can click SELECT ALL, if you wish to take all the master record values as final and merge the duplicates.
   
   If not, click the radio buttons near the corresponding fields of other records to instruct CRM on which field values should be considered "final" in order to merge duplicates.
   The values thus selected appear under the MASTER RECORD column.
3. Once you have resolved the conflicting values, click Merge.
   A warning message is displayed, informing you of the consequences of the merging of records. Once you are sure, confirm the action.
   The duplicates will successfully be merged as seen below.