issue when merging the cube with kylin-0.71

[dong wang]

hi, i design a cube with partition date attribute named my_date(be
mentioned in the previous email), no problem with incrementally building
the cube, however, when I select the "merge" menu item to merge the cube, a
popup window says: No partition date column defined. which puzzles me a lot
since I defined a data column as partition attribute for the cube actually~