diff --git a/core/modules/field/field.crud.inc b/core/modules/field/field.crud.inc
index 873ab55..8422600 100644
--- a/core/modules/field/field.crud.inc
+++ b/core/modules/field/field.crud.inc
@@ -520,7 +520,7 @@ function field_delete_instance(FieldInstance $instance, $field_cleanup = TRUE) {
 function field_purge_batch($batch_size) {
   // Retrieve all deleted field instances. We cannot use field_info_instances()
   // because that function does not return deleted instances.
-  $instances = field_read_instances(array('deleted' => 1), array('include_deleted' => 1));
+  $instances = field_read_instances(array('deleted' => TRUE), array('include_deleted' => TRUE));
   $factory = Drupal::service('entity.query');
   $info = entity_get_info();
   foreach ($instances as $instance) {
diff --git a/core/modules/field/field.install b/core/modules/field/field.install
index c1a1378..663ae69 100644
--- a/core/modules/field/field.install
+++ b/core/modules/field/field.install
@@ -32,8 +32,8 @@ function _update_7000_field_create_field(&$field) {
     'locked' => FALSE,
     'settings' => array(),
     'indexes' => array(),
-    'deleted' => 0,
-    'active' => 1,
+    'deleted' => FALSE,
+    'active' => TRUE,
   );
 
   // Set storage.
@@ -41,7 +41,7 @@ function _update_7000_field_create_field(&$field) {
     'type' => 'field_sql_storage',
     'settings' => array(),
     'module' => 'field_sql_storage',
-    'active' => 1,
+    'active' => TRUE,
   );
 
   // Fetch the field schema to initialize columns and indexes. The field module
@@ -208,7 +208,7 @@ function _update_7000_field_create_instance($field, &$instance) {
   $instance += array(
     'field_id' => $field['id'],
     'field_name' => $field['field_name'],
-    'deleted' => 0,
+    'deleted' => FALSE,
     'description' => '',
     'required' => FALSE,
   );
diff --git a/core/modules/field/lib/Drupal/field/Plugin/Core/Entity/Field.php b/core/modules/field/lib/Drupal/field/Plugin/Core/Entity/Field.php
index 0180dd4..18a35cb 100644
--- a/core/modules/field/lib/Drupal/field/Plugin/Core/Entity/Field.php
+++ b/core/modules/field/lib/Drupal/field/Plugin/Core/Entity/Field.php
@@ -235,7 +235,7 @@ public function __construct(array $values, $entity_type = 'field_entity') {
       'translatable' => FALSE,
       'entity_types' => array(),
       'locked' => FALSE,
-      'deleted' => 0,
+      'deleted' => FALSE,
       'storage' => array(),
       'indexes' => array(),
     );
diff --git a/core/modules/field/lib/Drupal/field/Plugin/Core/Entity/FieldInstance.php b/core/modules/field/lib/Drupal/field/Plugin/Core/Entity/FieldInstance.php
index 9db2f3d..24e3df4 100644
--- a/core/modules/field/lib/Drupal/field/Plugin/Core/Entity/FieldInstance.php
+++ b/core/modules/field/lib/Drupal/field/Plugin/Core/Entity/FieldInstance.php
@@ -273,7 +273,7 @@ public function __construct(array $values, $entity_type = 'field_instance') {
       'default_value_function' => '',
       'settings' => array(),
       'widget' => array(),
-      'deleted' => 0,
+      'deleted' => FALSE,
     );
     parent::__construct($values, $entity_type);
   }
diff --git a/core/modules/field/lib/Drupal/field/Plugin/views/field/Field.php b/core/modules/field/lib/Drupal/field/Plugin/views/field/Field.php
index f4b564f..c288750 100644
--- a/core/modules/field/lib/Drupal/field/Plugin/views/field/Field.php
+++ b/core/modules/field/lib/Drupal/field/Plugin/views/field/Field.php
@@ -451,7 +451,7 @@ function fakeFieldInstance($formatter, $formatter_settings) {
       'required' => FALSE,
       'label' => $field_name,
       'description' => '',
-      'deleted' => 0,
+      'deleted' => FALSE,
     );
   }
 
diff --git a/core/modules/field/lib/Drupal/field/Tests/BulkDeleteTest.php b/core/modules/field/lib/Drupal/field/Tests/BulkDeleteTest.php
index 9b03174..ca414bc 100644
--- a/core/modules/field/lib/Drupal/field/Tests/BulkDeleteTest.php
+++ b/core/modules/field/lib/Drupal/field/Tests/BulkDeleteTest.php
@@ -166,7 +166,7 @@ function testDeleteFieldInstance() {
     field_delete_instance($instance);
 
     // The instance still exists, deleted.
-    $instances = field_read_instances(array('field_id' => $field['uuid'], 'deleted' => 1), array('include_deleted' => 1, 'include_inactive' => 1));
+    $instances = field_read_instances(array('field_id' => $field['uuid'], 'deleted' => TRUE), array('include_deleted' => TRUE, 'include_inactive' => TRUE));
     $this->assertEqual(count($instances), 1, 'There is one deleted instance');
     $this->assertEqual($instances[0]['bundle'], $bundle, 'The deleted instance is for the correct bundle');
 
@@ -193,7 +193,7 @@ function testDeleteFieldInstance() {
       $ids->entity_id = $entity_id;
       $entities[$entity_id] = _field_create_entity_from_ids($ids);
     }
-    field_attach_load($this->entity_type, $entities, FIELD_LOAD_CURRENT, array('field_id' => $field['uuid'], 'deleted' => 1));
+    field_attach_load($this->entity_type, $entities, FIELD_LOAD_CURRENT, array('field_id' => $field['uuid'], 'deleted' => TRUE));
     $this->assertEqual(count($found), 10, 'Correct number of entities found after deleting');
     foreach ($entities as $id => $entity) {
       $this->assertEqual($this->entities[$id]->{$field['field_name']}, $entity->{$field['field_name']}, "Entity $id with deleted data loaded correctly");
@@ -249,18 +249,18 @@ function testPurgeInstance() {
     $this->checkHooksInvocations($hooks, $actual_hooks);
 
     // The instance still exists, deleted.
-    $instances = field_read_instances(array('field_id' => $field['uuid'], 'deleted' => 1), array('include_deleted' => 1, 'include_inactive' => 1));
+    $instances = field_read_instances(array('field_id' => $field['uuid'], 'deleted' => TRUE), array('include_deleted' => TRUE, 'include_inactive' => TRUE));
     $this->assertEqual(count($instances), 1, 'There is one deleted instance');
 
     // Purge the instance.
     field_purge_batch($batch_size);
 
     // The instance is gone.
-    $instances = field_read_instances(array('field_id' => $field['uuid'], 'deleted' => 1), array('include_deleted' => 1, 'include_inactive' => 1));
+    $instances = field_read_instances(array('field_id' => $field['uuid'], 'deleted' => TRUE), array('include_deleted' => TRUE, 'include_inactive' => TRUE));
     $this->assertEqual(count($instances), 0, 'The instance is gone');
 
     // The field still exists, not deleted, because it has a second instance.
-    $fields = field_read_fields(array('uuid' => $field['uuid']), array('include_deleted' => 1, 'include_inactive' => 1));
+    $fields = field_read_fields(array('uuid' => $field['uuid']), array('include_deleted' => TRUE, 'include_inactive' => TRUE));
     $this->assertTrue(isset($fields[$field['uuid']]), 'The field exists and is not deleted');
   }
 
@@ -302,7 +302,7 @@ function testPurgeField() {
     field_purge_batch(0);
 
     // The field still exists, not deleted.
-    $fields = field_read_fields(array('uuid' => $field['uuid']), array('include_deleted' => 1));
+    $fields = field_read_fields(array('uuid' => $field['uuid']), array('include_deleted' => TRUE));
     $this->assertTrue(isset($fields[$field['uuid']]) && !$fields[$field['uuid']]->deleted, 'The field exists and is not deleted');
 
     // Delete the second instance.
@@ -326,14 +326,14 @@ function testPurgeField() {
     $this->checkHooksInvocations($hooks, $actual_hooks);
 
     // The field still exists, deleted.
-    $fields = field_read_fields(array('uuid' => $field['uuid']), array('include_deleted' => 1));
+    $fields = field_read_fields(array('uuid' => $field['uuid']), array('include_deleted' => TRUE));
     $this->assertTrue(isset($fields[$field['uuid']]) && $fields[$field['uuid']]->deleted, 'The field exists and is deleted');
 
     // Purge again to purge the instance and the field.
     field_purge_batch(0);
 
     // The field is gone.
-    $fields = field_read_fields(array('uuid' => $field['uuid']), array('include_deleted' => 1, 'include_inactive' => 1));
+    $fields = field_read_fields(array('uuid' => $field['uuid']), array('include_deleted' => TRUE, 'include_inactive' => TRUE));
     $this->assertEqual(count($fields), 0, 'The field is purged.');
   }
 }