MDL-29520 - mysql multitable delete, outer join some tables

reskit · Oct 9, 2011 · 033d656 · 033d656
1 parent 9086337
commit 033d656
Showing 1 changed file with 3 additions and 3 deletions.
diff --git a/question/engine/datalib.php b/question/engine/datalib.php
@@ -695,8 +695,8 @@ protected function delete_usage_records_for_mysql(qubaid_condition $qubaids) {
                 DELETE qu, qa, qas, qasd
                   FROM {question_usages}            qu
                   JOIN {question_attempts}          qa   ON qa.questionusageid = qu.id
-                  JOIN {question_attempt_steps}     qas  ON qas.questionattemptid = qa.id
-                  JOIN {question_attempt_step_data} qasd ON qasd.attemptstepid = qas.id
+             LEFT JOIN {question_attempt_steps}     qas  ON qas.questionattemptid = qa.id
+             LEFT JOIN {question_attempt_step_data} qasd ON qasd.attemptstepid = qas.id
                  WHERE qu.id ' . $qubaids->usage_id_in(),
                 $qubaids->usage_id_in_params());
     }
@@ -713,7 +713,7 @@ protected function delete_attempt_steps_for_mysql($test, $params) {
         $this->db->execute('
                 DELETE qas, qasd
                   FROM {question_attempt_steps}     qas
-                  JOIN {question_attempt_step_data} qasd ON qasd.attemptstepid = qas.id
+             LEFT JOIN {question_attempt_step_data} qasd ON qasd.attemptstepid = qas.id
                  WHERE qas.questionattemptid ' . $test, $params);
     }