Marketing Cloud Developers Certification Practice Test

Focus on how data writes work in CloudPages, microsites, CloudPages, and MobileConnect. When you’re collecting user inputs on a landing page or via SMS and you want to persist that data to a Data Extension, you often need to either add a new row or update an existing one in a single operation. UpsertData does exactly that: it upserts a row based on a key field, inserting if it doesn’t exist and updating if it does. This behavior is ideal for landing pages and MobileConnect interactions where you want to avoid duplicate records and keep data current.

In practice, you define a primary key on the Data Extension and pass the field values to UpsertData. If a row with the key already exists, the function updates the specified fields; if not, it creates a new row. That single-call upsert is why this function is the one used in these contexts.

Other functions either insert only (which can create duplicates) or are not appropriate for CloudPages/MobileConnect workflows, so they aren’t used in these scenarios.