According to https://jira.sakaiproject.org/browse/SAK-30644 the isUserSubmission attribute could be not present in some submissions. So if the attribute is not present you must consider other things to get the correct value for it.
I think the assignment conversion job is not handling this properly and is moving always to false. The result is you get a lot of "0/0" values in assignment list.
This issue revolves around these 3 issues (copied from below):
- isUserSubmission: We've found some XML's without this attribute, after the migration the USER_SUBMISSION is 0, and the result is that the summary count is always 0/0. In Sakai 11 this is not 0/0 even the XML has no isUserSubmission attribute, due to this code
- submitter0..9: We've found also XML's without this attribute, after migration only one member appears associated with the group submission. This is because a side effect in Sakai 11. The sumitter0..9 attribute is included in the XML when the instructor access to the submission not when the student make the submission (pretty annoying).
- Individual submissions: The last thing we've found. If you create a group assignment and press the "Grade Report" button in Sakai 11, the system add one submission for each group and also one submission for each member of the group (WTF!!). So when you try to migrate submissions you could get some rows that belongs to individuals not group, even the assignment is a group assignment.