The Qlik Replicate developer notices that errors occur about the duplicate key when applying INSERT. Which should be done in order to identify this…

The Apply Exceptions control table (attrepapplyexceptions) is the designated mechanism within Qlik Replicate for logging records that fail to be applied to the target database. When an INSERT operation fails due to a "duplicate key" error, Replicate captures the entire failed record, the operation type, the time of the error, and the specific error message from the target database. By querying this table, the developer can directly identify the exact row and data that caused the conflict, which is the essential first step in diagnosing the root cause of the issue.

B. Stop and reload the task: This is a recovery method that overwrites the target data, but it does not help identify the specific record or reason for the original error.

C. Stop task and enable the Apply Exceptions control table: While enabling this table is necessary to capture exceptions, the question implies errors are already occurring; the immediate action to identify the issue is to check the log, not configure it.

D. Stop and resume the task: Resuming the task will simply cause Replicate to retry the same failed operation, leading to the same duplicate key error without providing any new diagnostic information.

1. Qlik Replicate User Guide, "Control Tables" section, "Transaction and exception tables" subsection: The documentation explicitly describes the attrepapplyexceptions table. It states, "Stores information about records that could not be applied to the target. The records are stored in the table in CSV format." This confirms it is the primary location for investigating apply-phase errors.

2. Qlik Replicate User Guide, "Error Handling" section, "Apply Conflicts" subsection: This section details how Replicate handles data conflicts such as primary key collisions during INSERT operations. It explains that one of the resolution actions is to "Log the record in the exceptions table," reinforcing that this table is the correct place to look for such errors.

3. Qlik Help Portal, "Viewing and handling exceptions": This documentation page provides instructions on how to manage exceptions. It states, "When a record cannot be applied to a target table... Replicate writes the record to the Apply Exceptions (attrepapplyexceptions) control table." This directly supports using the table to identify the issue.