Cannot insert duplicate key in object

RE: Cannot insert duplicate key in object

subhankar-Maantic — Thu, 04 Jun 2026 05:48:26 GMT

Appian is attempting to INSERT a new row into INVOICE_PAYMENT_INFO instead of UPDATE the existing one — because the PK of INVOICE_PAYMENT_INFO is null during the write operation.

The constraint UQ_PAYMENT_INFO_HEADER_INVOICE_ID is on INVOICE_ID — not the PK. So even though PK is blank, the duplicate is caught on INVOICE_ID = 21769 which already exists.

RE: Cannot insert duplicate key in object

Shubham Aware — Thu, 04 Jun 2026 05:39:12 GMT

Most probably unique constraint UQ_PAYMENT_INFO_HEADER_INVOICE_ID is on the invoice_id column, and a row with invoice_id = 21769 already exists in INVOICE_PAYMENT_INFO.
For 1:1 relationships, Write Records inserts a new child when PK is blank; but your FK (invoice_id) duplicates an existing row. Fetch the existing child record first and pass its PK so Write Records performs an update instead of insert.