The PDSE directory can contain attributes in addition to those traditionally kept in a partitioned data set directory entry.

Some PDSE extended attributes are recorded on an unload data set and will be reloaded when the target is a PDSE.

If you reload an unloaded PDSE that contains program objects to a partitioned data set, an error message is issued and the operation fails.

Information that is kept as user data in a partitioned data set directory, such as PDF statistics, will move to a PDSE directory and back from a PDSE directory to a partitioned data set directory without change.