Marketing Cloud Engagement Basics22% of the exam
Subscriber keys, contact keys and contact IDs
Why subscriber key and contact key are one value you choose, why the Contact ID is a back-end number, how to pick a stable key, what the key lets you do, and why contacts outnumber subscribers.
Differentiate between subscriber keys, contact keys, and contact IDs to uniquely identify subscribers.
~5 min read · 7 practice questions ·
What the exam expects
- Explain that subscriber key and contact key are the same value, named differently by Email Studio and Contact Builder.
- Distinguish the key you assign from the Contact ID that Salesforce assigns on the back end.
- Choose a unique, stable, non-channel value as the key, such as the 18-digit Salesforce record ID.
- List what a subscriber key makes possible, and predict what inconsistent keys do to contact counts.
- Explain why every subscriber is a contact but not every contact is a subscriber.
- Key terms: subscriber key (the value you choose that uniquely identifies a subscriber); contact key (the same value in Contact Builder, constant across channels); Contact ID (a number Salesforce uses to identify a contact on the back end); contact (anyone you message on any channel); subscriber (a person who opted in to or belongs to a channel).
Key facts
Two names, one value
- Detail
- Subscriber key in Email Studio, contact key in Contact Builder
Contact ID
- Detail
- Back-end number Salesforce uses
Key length
- Detail
- Up to 254 English characters
Email as key
- Detail
- Avoid it
Salesforce records
- Detail
- 18-digit ID stored as the key during Connect sends
All Subscribers entry
- Detail
- Only after something is sent
Sendable data extensions
- Detail
- Must contain the subscriber key
- What is the maximum length of a subscriber key?
- When you import or create a subscriber, what does Engagement use the subscriber key to decide?
- When you export subscribers, which value appears in the output whatever criteria you searched on?
- Why would a loyalty ID such as "GX(7781)" fail as a subscriber key?
The questions are free to read. Answers with their sources and self-grading are included with the pack.
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