diff --git a/core/Migrations/Version13000Date20170718121200.php b/core/Migrations/Version13000Date20170718121200.php
index ffd230e19adb9d1ae1cd55d1633a53aa1549a453..3acdc3122e3659ddff6f2138bd99abe79de31e49 100644
--- a/core/Migrations/Version13000Date20170718121200.php
+++ b/core/Migrations/Version13000Date20170718121200.php
@@ -518,12 +518,6 @@ class Version13000Date20170718121200 extends SimpleMigrationStep {
 			]);
 			$table->setPrimaryKey(['id']);
 			$table->addIndex(['class'], 'job_class_index');
-		} else {
-			$table = $schema->getTable('jobs');
-			$table->changeColumn('execution_duration', [
-				'notnull' => true,
-				'default' => 0,
-			]);
 		}
 
 		if (!$schema->hasTable('users')) {
@@ -576,25 +570,25 @@ class Version13000Date20170718121200 extends SimpleMigrationStep {
 				'default' => '',
 			]);
 			$table->addColumn('type', 'smallint', [
-				'notnull' => true,
+				'notnull' => false,
 				'length' => 2,
 				'default' => 0,
 				'unsigned' => true,
 			]);
 			$table->addColumn('remember', 'smallint', [
-				'notnull' => true,
+				'notnull' => false,
 				'length' => 1,
 				'default' => 0,
 				'unsigned' => true,
 			]);
 			$table->addColumn('last_activity', 'integer', [
-				'notnull' => true,
+				'notnull' => false,
 				'length' => 4,
 				'default' => 0,
 				'unsigned' => true,
 			]);
 			$table->addColumn('last_check', 'integer', [
-				'notnull' => true,
+				'notnull' => false,
 				'length' => 4,
 				'default' => 0,
 				'unsigned' => true,
diff --git a/core/Migrations/Version13000Date20170919121250.php b/core/Migrations/Version13000Date20170919121250.php
index 284a509f5a287aa21c523ada3e071b3e8ca27685..0667ea873396470301952e1a653a6802eb32c99e 100644
--- a/core/Migrations/Version13000Date20170919121250.php
+++ b/core/Migrations/Version13000Date20170919121250.php
@@ -68,7 +68,7 @@ class Version13000Date20170919121250 extends SimpleMigrationStep {
 			$column->setUnsigned(true);
 		} else {
 			$table->addColumn('remember', 'smallint', [
-				'notnull' => true,
+				'notnull' => false,
 				'length' => 1,
 				'default' => 0,
 				'unsigned' => true,
diff --git a/core/Migrations/Version21000Date20201120141228.php b/core/Migrations/Version21000Date20201120141228.php
index 48c924977d0419502e32263d39af77ebda9a4254..844679b8d95c465bc1f275ff5889463831b5e344 100644
--- a/core/Migrations/Version21000Date20201120141228.php
+++ b/core/Migrations/Version21000Date20201120141228.php
@@ -20,6 +20,18 @@ class Version21000Date20201120141228 extends SimpleMigrationStep {
 			if ($loginNameColumn->getLength() !== 255) {
 				$loginNameColumn->setLength(255);
 			}
+			$table->changeColumn('type', [
+				'notnull' => false,
+			]);
+			$table->changeColumn('remember', [
+				'notnull' => false,
+			]);
+			$table->changeColumn('last_activity', [
+				'notnull' => false,
+			]);
+			$table->changeColumn('last_check', [
+				'notnull' => false,
+			]);
 		}
 
 		if ($schema->hasTable('dav_job_status')) {
@@ -40,6 +52,14 @@ class Version21000Date20201120141228 extends SimpleMigrationStep {
 			}
 		}
 
+		if ($schema->hasTable('jobs')) {
+			$table = $schema->getTable('jobs');
+			$table->changeColumn('execution_duration', [
+				'notnull' => false,
+				'default' => 0,
+			]);
+		}
+
 		return $schema;
 	}
 }