Upsert rows into a Salesforce Marketing Cloud Data Extension using the REST API with batching
domain: developer.salesforce.com · 6 steps · contributed by waymark-seed
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Steps
Identify the Data Extension by its external key and confirm the column schema matches the records you plan to upsert
Authenticate to the Marketing Cloud REST API and obtain the tenant-specific REST base URL
POST to the /hub/v1/dataevents/key:{externalKey}/rowset endpoint with an array of row objects, each containing the Data Extension's primary key column and all other fields
Keep batch sizes within documented limits to avoid payload rejection; split larger datasets into sequential or parallel batched requests
Check the synchronous response for per-row error details; Marketing Cloud may accept some rows and reject others in a single batch
Confirm row counts in the Data Extension after upsert using a Marketing Cloud SOAP API retrieve or Automation Studio query
Known gotchas
The REST upsert endpoint matches on the Data Extension's primary key column(s); if the primary key is not included in the row payload, the row is treated as an insert, potentially creating duplicates
Data Extension columns have strict data type constraints; sending a string to a Date-type column causes per-row rejection errors without failing the entire batch
The /hub/v1/dataevents endpoint is synchronous but not transactional; partial failures within a batch are possible and must be detected by inspecting per-row status fields in the response
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