When you perform an array update or upsert to an Oracle target, the following issues occur:

If the primary key is not defined in the Oracle target, the number of applied and reject rows count is incorrect.
If the target field you specify as the update column in the mapping contains duplicate records, data mismatch occurs.

Workaround: The target field you specify as the update column in the mapping must not contain duplicate records. (October 2020)

Progress ticket number: 00858178