KSDS edit

A VSAM KSDS file has the ability to insert and delete records without requiring them to be in sequence (as they are sequenced by VSAM in their key order). Hence applications intending to add, change, or remove records (such as File Manager) do not need to keep the entire file contents available (in order to rewrite the entire file) when saving changes. For KSDS files, File Manager only keeps new, changed, or deleted records in storage, as well as those currently being displayed. This is why File Manager can edit a KSDS file of any size without needing to employ the auxiliary edit technique described earlier.

When File Manager uses this editing technique, it displays "Edit" in the top left of the editor panel title line.