Slice.druid_datasource_id empty in older versions

[x4base]

I am using the sqlite file from an older version of panoramix (about v0.8.0 f0b2f98).
Even after I run caravel db upgrade,slices.druid_datasource_id are all empty.
The table druid_datasource is also empty.
Seems like I have to refresh the druid datasource to create new records in the table datasources. Is it the only way to fix this? Can it be fixed using the migration script?
Otherwise, it will make Slice.druid_datasource and Slice.datasource empty, causing other errors.
For example:

File "caravel/views.py", line 651, in dashboard
pos_dict=pos_dict)
...
File "caravel/templates/caravel/dashboard.html", line 80, in block "body"
class="widget {{ slice.viz.viz_type }}"
File "lib/python2.7/site-packages/Jinja2-2.8-py2.7.egg/jinja2/environment.py", line 408, in getattr
return getattr(obj, attribute)
UndefinedError: 'caravel.models.Slice object' has no attribute 'viz'