If a quiz is set to have a grace period when time has expired, we only
email studnets to warn them about their overdue attempt if they have put
in an answer to at least one question that is worth some marks.
While doing this code clean-up, I noticed that the question bank pop-up was
only showing the question name, whereas it should have been showing the
question name and the start of the question text, so I fixed that.
This patch adds completion options to Quiz similar to what is available in scorm.
One can have the quiz marked complete when either a passing grade is achieved or
all attempts are used up. This will allow a quiz to complete when the user "passes
or fails". (Where "fail" means "using up all attempts without passing".)
The sequence of questions that made up a quiz used to be stored as a
comma-separated list in quiz.questions. Now the same information is
stored in the rows in the quiz_slots table. This is not just 'better' in
a database design sense, but it allows for the future changes we will
need as we enhance the quiz in the MDL-40987 epic.
Having changed the database structure, all the rest of the code needs to
be changed to account for it, and that is done here.
Note that there are not many unit tests for the changed bit. That is
because as part of MDL-40987 we will be changing the code further, and
we will add unit tests then.
This data should all have been upgraded when moving to Moodle 2.1. It
was only kept as a back-up, and now, after 3 years have past, we can
clean it up.
Some columns needed to be renamed:
* quiz -> quizid
* question -> questionid
* grade -> maxmark
Then all the places that refer to those needed to be fixed.
Melinda Kraft reported having rows in their quiz_question_instances
table which caused various problems. These rows are meaningless, so I
have done a DB upgrade step to clean them up, which should deal with the
bad side-effets they were causing.
... before trying to create the unique index that should be there.
The violations may come from old buggy code.
We do two things.
1. First we delete all previews.
2. Then, if there are still problems, we renumber attempts to eliminate
the duplicates.
