When Extract starts for the first time to begin capturing data during the instantiation process, it captures all of the transaction data that it encounters after the specified start point, but none of the data that occurred before that point. To ensure that Extract does not start in the middle of ongoing transactions that would be discarded, set the tables that are to be captured to an inactive state. You can either put the system into a restricted state by using the ALCOBJ command to lock the objects or libraries, or you can force all of the current transactions on those tables to stop at a certain point.

After initialization is complete, remember to unlock any objects that you locked. To do so, log off of the session that locked the objects or use the DLCOBJ command from the OS/400 command line.