diff --git a/lib/db/install.xml b/lib/db/install.xml
index a40a4c03fdf..6b361f5d63c 100644
--- a/lib/db/install.xml
+++ b/lib/db/install.xml
@@ -1453,7 +1453,7 @@
         <FIELD NAME="questionbankentryid" TYPE="int" LENGTH="10" NOTNULL="true" DEFAULT="0" SEQUENCE="false" COMMENT="ID of the question bank entry this question version is part of."/>
         <FIELD NAME="version" TYPE="int" LENGTH="10" NOTNULL="true" DEFAULT="1" SEQUENCE="false" COMMENT="Version number for the question where the first version is always 1."/>
         <FIELD NAME="questionid" TYPE="int" LENGTH="10" NOTNULL="true" DEFAULT="0" SEQUENCE="false" COMMENT="The question ID."/>
-        <FIELD NAME="status" TYPE="char" LENGTH="10" NOTNULL="false" DEFAULT="ready" SEQUENCE="false" COMMENT="If the question is ready, hidden or draft"/>
+        <FIELD NAME="status" TYPE="char" LENGTH="10" NOTNULL="true" DEFAULT="ready" SEQUENCE="false" COMMENT="If the question is ready, hidden or draft"/>
       </FIELDS>
       <KEYS>
         <KEY NAME="primary" TYPE="primary" FIELDS="id"/>
diff --git a/lib/db/upgrade.php b/lib/db/upgrade.php
index d3a195daa16..c35ae1f2b08 100644
--- a/lib/db/upgrade.php
+++ b/lib/db/upgrade.php
@@ -3844,7 +3844,7 @@ privatefiles,moodle|/user/files.php';
 
         // Adding fields to table question_versions.
         $table->add_field('id', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, XMLDB_SEQUENCE, null);
-        $table->add_field('questionbankentryid', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, null);
+        $table->add_field('questionbankentryid', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, 0);
         $table->add_field('version', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, 1);
         $table->add_field('questionid', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, 0);
         $table->add_field('status', XMLDB_TYPE_CHAR, '10', null, XMLDB_NOTNULL, null, 'ready');
@@ -3867,8 +3867,8 @@ privatefiles,moodle|/user/files.php';
         $table->add_field('usingcontextid', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, 0);
         $table->add_field('component', XMLDB_TYPE_CHAR, '100', null, null, null, null);
         $table->add_field('questionarea', XMLDB_TYPE_CHAR, '50', null, null, null, null);
-        $table->add_field('itemid', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, null);
-        $table->add_field('questionbankentryid', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, null);
+        $table->add_field('itemid', XMLDB_TYPE_INTEGER, '10', null, null, null, null);
+        $table->add_field('questionbankentryid', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, 0);
         $table->add_field('version', XMLDB_TYPE_INTEGER, '10', null, null, null, null);
 
         // Adding keys to table question_references.
@@ -3889,14 +3889,13 @@ privatefiles,moodle|/user/files.php';
         $table->add_field('usingcontextid', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, 0);
         $table->add_field('component', XMLDB_TYPE_CHAR, '100', null, null, null, null);
         $table->add_field('questionarea', XMLDB_TYPE_CHAR, '50', null, null, null, null);
-        $table->add_field('itemid', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, null);
+        $table->add_field('itemid', XMLDB_TYPE_INTEGER, '10', null, null, null, null);
         $table->add_field('questionscontextid', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, 0);
         $table->add_field('filtercondition', XMLDB_TYPE_TEXT, null, null, null, null, null);
 
         // Adding keys to table question_set_references.
         $table->add_key('primary', XMLDB_KEY_PRIMARY, ['id']);
         $table->add_key('usingcontextid', XMLDB_KEY_FOREIGN, ['usingcontextid'], 'context', ['id']);
-        $table->add_key('itemid', XMLDB_KEY_FOREIGN, ['itemid'], 'quiz_slots', ['id']);
         $table->add_key('questionscontextid', XMLDB_KEY_FOREIGN, ['questionscontextid'], 'context', ['id']);
 
         // Conditionally launch create table for question_set_references.