When you work with a significant 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 duplicate entries increase as well. For example, the same lead may be created via import as well as via APIs. Zoho CRM has a built-in tools to check duplicate and merge them. However this is limited to Leads, Contacts, Accounts and Vendors modules.
For custom modules, A1CRM created a find and merge duplicates tool that allows user to enter further criteria to search for duplicates. Identified records can be automatically merged or notify user to manually merge. The duplicate records are then automatically deleted or marked to delete. This is very helpful in maintaining records in your custom modules.