Question

A data analyst is preparing a customer contact list merged from two CRM exports. The same customer sometimes appears twice: once with an email of 'JSmith@Corp.com' and once as 'jsmith@corp.com', but with identical phone numbers and mailing addresses. A simple deduplication on the exact email string leaves both records in the dataset. What is the MOST effective approach to identify and remove these duplicate records?

Accepted Answer

Standardize the email field to lowercase before applying deduplication logic across matching fields

Answer

Delete every record that has a missing value in any column to reduce list size

Answer

Sort the dataset alphabetically by last name and manually review the entire file

Answer

Apply min-max normalization to the phone number column to expose duplicates