When migrating customer contacts, which combination of identifiers will help ensure unique records are entered?

The most effective combination of identifiers to ensure unique records during the migration of customer contacts is the pairing of first name, last name, and customer ID. When dealing with customer records, it's crucial to have a reliable means of identification that can uniquely distinguish one customer from another.

While first names and last names can often lead to duplicates, especially in cases where common names are involved, the addition of a customer ID provides a distinct and unique identifier that is specific to each individual record. The customer ID is typically an autogenerated or assigned identifier that signifies one unique record in the database, thus greatly minimizing the risk of entering duplicate contacts.

Other combinations such as phone numbers or email addresses may also be useful but can sometimes lead to inaccuracies. For example, individuals can change their phone numbers or use multiple email addresses, which might result in creating duplicate records. Similarly, a street address may not be unique enough, especially in densely populated areas, leading to confusion during record migration.

Thus, using first name, last name, and customer ID is the optimal choice for ensuring the integrity and uniqueness of customer records during migration.