Specifying Replacement on the Data Set Level

When you merge partitioned data sets, or load an unload data set into a partitioned data set that already has members, the input and output data sets might have members with the same names. Under normal processing, these input members will not replace the output members that have their names. To specify that all input members are to be copied to the output data set, and thus replace any output members of the same name, use the replace (R) option on an INDD or COPY statement.

When replace (R) is specified on the data set level, the input data is processed as follows:

In a full copy or load process, all members in an input data set are copied to an output partitioned data set; members whose names already exist in the output partitioned data set are replaced by members copied or loaded from the input data set.
In a selective copy or load process, all selected input members will be copied to the output data set, replacing any identically named output data set members. Specifying replace (R) on the data set level when performing a selective copy relieves you of the need to specify replace (R) for each member you want copied.
In an exclusive copy process, all nonexcluded members on the input data sets are copied or loaded to an output partitioned data set, replacing those members with duplicate names on the output partitioned data set.