A Clarity table's primary key includes a CSN. What does this mean?

• A. CSN stands for Customer Serial Number.
• B. CSN stands for Confidential Serial Number.
• C. CSN indicates a deprecated field.
• D. A CSN is a Contact Serial Number, identifying a specific contact within a specific record. A table with a CSN in its primary key extracts overtime data - if it extracted no-add data, you wouldn't need to identify a contact.

Answer: (D)

The key idea is per-contact granularity in a table. CSN here stands for Contact Serial Number, which identifies a specific contact within a particular record. Including this in the primary key makes each row unique not just by the record itself, but by the exact person tied to that record. That’s essential when the data is or is used per-contact—for example, overtime data that varies by who the contact is within the record. If the data weren’t tied to a specific contact, there’d be no need to identify the contact in the key. Since CSN refers to a contact identifier, it’s not the Customer Serial Number or Confidential Serial Number, and there’s no implication that the field is deprecated.