Add composite index for PeerWorkflow (course_id, item_id, student_id).

apps/openassessment/assessment/migrations/0003_add_index_pw_course_item_student.py

+# -*- coding: utf-8 -*-
+import datetime
+from south.db import db
+from south.v2 import SchemaMigration
+from django.db import models
+
+
+class Migration(SchemaMigration):
+
+    def forwards(self, orm):
+        # Adding index on 'PeerWorkflow', fields ['course_id']
+        db.create_index('assessment_peerworkflow', ['course_id', 'item_id', 'student_id'])
+
+
+    def backwards(self, orm):
+        # Removing index on 'PeerWorkflow', fields ['course_id']
+        db.delete_index('assessment_peerworkflow', ['course_id', 'item_id', 'student_id'])
+
+
+    models = {
+        'assessment.assessment': {
+            'Meta': {'ordering': "['-scored_at', '-id']", 'object_name': 'Assessment'},
+            'feedback': ('django.db.models.fields.TextField', [], {'default': "''", 'max_length': '10000', 'blank': 'True'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'rubric': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['assessment.Rubric']"}),
+            'score_type': ('django.db.models.fields.CharField', [], {'max_length': '2'}),
+            'scored_at': ('django.db.models.fields.DateTimeField', [], {'default': 'datetime.datetime.now', 'db_index': 'True'}),
+            'scorer_id': ('django.db.models.fields.CharField', [], {'max_length': '40', 'db_index': 'True'}),
+            'submission_uuid': ('django.db.models.fields.CharField', [], {'max_length': '128', 'db_index': 'True'})
+        },
+        'assessment.assessmentfeedback': {
+            'Meta': {'object_name': 'AssessmentFeedback'},
+            'assessments': ('django.db.models.fields.related.ManyToManyField', [], {'default': 'None', 'related_name': "'assessment_feedback'", 'symmetrical': 'False', 'to': "orm['assessment.Assessment']"}),
+            'feedback_text': ('django.db.models.fields.TextField', [], {'default': "''", 'max_length': '10000'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'options': ('django.db.models.fields.related.ManyToManyField', [], {'default': 'None', 'related_name': "'assessment_feedback'", 'symmetrical': 'False', 'to': "orm['assessment.AssessmentFeedbackOption']"}),
+            'submission_uuid': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '128', 'db_index': 'True'})
+        },
+        'assessment.assessmentfeedbackoption': {
+            'Meta': {'object_name': 'AssessmentFeedbackOption'},
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'text': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '255'})
+        },
+        'assessment.assessmentpart': {
+            'Meta': {'object_name': 'AssessmentPart'},
+            'assessment': ('django.db.models.fields.related.ForeignKey', [], {'related_name': "'parts'", 'to': "orm['assessment.Assessment']"}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'option': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['assessment.CriterionOption']"})
+        },
+        'assessment.criterion': {
+            'Meta': {'ordering': "['rubric', 'order_num']", 'object_name': 'Criterion'},
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'name': ('django.db.models.fields.CharField', [], {'max_length': '100'}),
+            'order_num': ('django.db.models.fields.PositiveIntegerField', [], {}),
+            'prompt': ('django.db.models.fields.TextField', [], {'max_length': '10000'}),
+            'rubric': ('django.db.models.fields.related.ForeignKey', [], {'related_name': "'criteria'", 'to': "orm['assessment.Rubric']"})
+        },
+        'assessment.criterionoption': {
+            'Meta': {'ordering': "['criterion', 'order_num']", 'object_name': 'CriterionOption'},
+            'criterion': ('django.db.models.fields.related.ForeignKey', [], {'related_name': "'options'", 'to': "orm['assessment.Criterion']"}),
+            'explanation': ('django.db.models.fields.TextField', [], {'max_length': '10000', 'blank': 'True'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'name': ('django.db.models.fields.CharField', [], {'max_length': '100'}),
+            'order_num': ('django.db.models.fields.PositiveIntegerField', [], {}),
+            'points': ('django.db.models.fields.PositiveIntegerField', [], {})
+        },
+        'assessment.peerworkflow': {
+            'Meta': {'ordering': "['created_at', 'id']", 'object_name': 'PeerWorkflow'},
+            'completed_at': ('django.db.models.fields.DateTimeField', [], {'null': 'True', 'db_index': 'True'}),
+            'course_id': ('django.db.models.fields.CharField', [], {'max_length': '40', 'db_index': 'True'}),
+            'created_at': ('django.db.models.fields.DateTimeField', [], {'default': 'datetime.datetime.now', 'db_index': 'True'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'item_id': ('django.db.models.fields.CharField', [], {'max_length': '128', 'db_index': 'True'}),
+            'student_id': ('django.db.models.fields.CharField', [], {'max_length': '40', 'db_index': 'True'}),
+            'submission_uuid': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '128', 'db_index': 'True'})
+        },
+        'assessment.peerworkflowitem': {
+            'Meta': {'ordering': "['started_at', 'id']", 'object_name': 'PeerWorkflowItem'},
+            'assessment': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['assessment.Assessment']", 'null': 'True'}),
+            'author': ('django.db.models.fields.related.ForeignKey', [], {'related_name': "'graded_by'", 'to': "orm['assessment.PeerWorkflow']"}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'scored': ('django.db.models.fields.BooleanField', [], {'default': 'False'}),
+            'scorer': ('django.db.models.fields.related.ForeignKey', [], {'related_name': "'graded'", 'to': "orm['assessment.PeerWorkflow']"}),
+            'started_at': ('django.db.models.fields.DateTimeField', [], {'default': 'datetime.datetime.now', 'db_index': 'True'}),
+            'submission_uuid': ('django.db.models.fields.CharField', [], {'max_length': '128', 'db_index': 'True'})
+        },
+        'assessment.rubric': {
+            'Meta': {'object_name': 'Rubric'},
+            'content_hash': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '40', 'db_index': 'True'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'})
+        }
+    }
+
+    complete_apps = ['assessment']
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