Hi Akshaya,
You can use the bulk update API to append values to an existing simple attribute. If the survivorship of the simple attribute is Aggregation then all existing values will be OV else only the latest value will be OV.
PFB the API sample used to achieve the same for a sample containing only a single crosswalk.
For details, you can refer the documentation link.
Bulk Update of AttributesAPI used: POST {{tenantURL}}/entities/_updateRequest Body:{"objects": {"filter": "(equals(type,'configuration/entityTypes/Individual') and equals(id,'4W5ff44')","excludeList": ["entities/KKK"]},"actions": [{"operationParameters": {"sourceTypes": ["LNKD"],"attributeURI": "configuration/entityTypes/Individual/attributes/FirstName","attributeValue": "Name3"},"operation": "AddAttribute"}]}------------------------------
Saquib Muslim
Accenture
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