what is SY-DATUM

data syThere is also a predefined data type sy, which can be used instead of the data type SYST of ABAP Dictionary. The table below shows the system fields which can be used in ABAPI have read many of previous postings relkated to a sy-subrc = 8 that I am getting when trying to open a dataset. Some say dataset name is too long, I do not have authority,