The Deduplication activity in an Adobe Campaign Classic workflow is specifically designed to identify and remove duplicate entries from a target population. To prevent sending a delivery to multiple recipients with the same email address, this activity is configured to use the email address field as the deduplication criterion. It processes the inbound population, identifies records with identical email addresses, and retains only a single record per unique email address for the subsequent delivery activity, thereby ensuring each email address receives the communication only once.

A union activity combines multiple target populations into one. It does not remove duplicates and can, in fact, increase their number if the same recipient exists in multiple inbound sets.

A change dimension activity alters the targeting dimension of the workflow's population (e.g., from profiles to transactions). It does not perform any deduplication of records.

A split activity is used for segmentation. It divides a single target population into multiple distinct subsets based on specified criteria, rather than removing duplicate entries.

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1. Adobe Experience League. (n.d.). Campaign Classic v7 Documentation: Deduplication.

Section: Workflows > Activities > Targeting activities > Deduplication.

Quote/Paraphrase: The documentation explicitly states

"The Deduplication activity lets you remove duplicates from the results of the upstream activities in the workflow." It further provides an example: "you can deduplicate on the email address or telephone number to send a single delivery per household." This directly supports using the deduplication activity on the email address field before a delivery.

2. Adobe Experience League. (n.d.). Campaign Classic v7 Documentation: Targeting activities.

Section: Workflows > Activities > Targeting activities.

Quote/Paraphrase: This overview page describes the purpose of various targeting activities. The description for Union confirms it "lets you group the result of several activities

" Split "lets you create subsets

" and Change dimension "lets you change the targeting dimension." None of these descriptions include functionality for removing duplicates based on a field value.