Dropping edge property drops edges 

For existing graph data created prior to DSE 5.0.5, dropping an edge property might drop the edge.

The DataStax Enterprise Help Center also provides troubleshooting information.

For existing graph data created prior to DSE 5.0.5, dropping an edge property might drop the edge, depending on the method used to create the edge property.
  • If the edge property was created at the same time as the edge label in previous DSE versions, dropping the edge property will drop the edge entirely.
  • If the edge property is created separately from the edge label in previous DSE versions, dropping the edge property will not drop the edge.

This issue is fixed in DSE 5.0.5, but data created prior to that version will continue to drop edges in an unexpected manner.