The primary condition in the ON clause must specify an equality condition with the primary index of the target table, and with its partitioning column if it is a row‑partitioned table. The expression must also be identical to the expression specified for the primary index and partitioning column in the INSERT specification. The specified primary index value must equal the primary index value (and partitioning column value if the target table has row partitioning) implied by the column values specified in the INSERT specification of the WHEN NOT MATCHED clause.