Fallback for unknown dask categories
@@ -145,7 +145,10 @@ class DaskInterface(PandasInterface):
if len(group_by) == 1:
column = columns.data[group_by[0]]
if column.dtype.name == 'category':
+ try:
indices = ((ind,) for ind in column.cat.categories)
+ except NotImplementedError:
+ indices = ((ind,) for ind in column.unique().compute())
else:
indices = ((ind,) for ind in column.unique().compute())
else:
