Thank you the explanation.
Asked in addition,
"(VLR-REACTORS :VLR-Object-Reactor)" and
"(vlax-ldata-delete "VL-REACTORS" "$DOC$")"
Whether has the connected relations,
because deletes "VL-REACTORS" the project data,
Also can affect "VLR-REACTORS" the project data.
Did not know "VLR-REACTORS" the project data originates,
whether is comes from "VL-REACTORS"?
Requests master help to answer, thanks ~