Thank you in advance for your help. I do not know why an applymap in a preceding load (map_Period) referencing a loaded field discarded in the preceding load (%Date_Key) still works.
Because %Date_Key is part of the input table (i.e. the second table LOAD and hence can be used in any function of the preceding load, regardless if the field is part of the output table (the resulting resident table).
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