diff --git a/core/lib/Drupal/Core/Entity/FieldableDatabaseStorageController.php b/core/lib/Drupal/Core/Entity/FieldableDatabaseStorageController.php
index 43eb437..bba9b11 100644
--- a/core/lib/Drupal/Core/Entity/FieldableDatabaseStorageController.php
+++ b/core/lib/Drupal/Core/Entity/FieldableDatabaseStorageController.php
@@ -10,6 +10,7 @@
 use Drupal\Core\Database\Connection;
 use Drupal\Core\Entity\EntityTypeInterface;
 use Drupal\Core\Entity\Query\QueryInterface;
+use Drupal\Core\Field\FieldDefinitionInterface;
 use Drupal\Core\Language\Language;
 use Drupal\Component\Utility\NestedArray;
 use Drupal\Component\Uuid\Uuid;
@@ -1502,8 +1503,6 @@ static public function _fieldColumnName(FieldConfigInterface $field, $column) {
    * @return array|null
    *   Returns the schema definitions for the entity type's tables. If the
    *   entity type does not have a schema, returns NULL.
-   *
-   * @throws \LogicException
    */
   public function getSchema($table_key = NULL) {
     $passed_table_key = $table_key;
@@ -1529,92 +1528,24 @@ public function getSchema($table_key = NULL) {
         'bundle' => $this->bundleKey,
         'uuid' => $this->uuidKey,
       ));
-
-      // Prepare a mapping of which fields should be stored on which table. This
-      // information depends on which table types are provided.
-      if (!isset($tables['data_table']) && !isset($tables['revision_table'])) {
-        // In the simplest case all fields are stored in the base table.
-        $field_table_mapping = array('base_table' => array_values($entity_keys));
-        $other_fields_tables = array('base_table');
-      }
-      elseif (!isset($tables['data_table']) && isset($tables['revision_table'])) {
-        // For non-translatable, revisionable entities the entity key fields
-        // except for ID and revision ID are only stored in the base table. The ID
-        // is stored in both the base table and the revision table and the
-        // revision ID is only stored in the revision table. Additionally, the
-        // default revision ID of an entity is tracked as the revision ID field in
-        // the base table.
-        // Other fields are stored in the in the revision table and other fields
-        // of the default revision are stored in the the base table.
-        $field_table_mapping = array(
-          'base_table' => array_values($entity_keys),
-          'revision_table' => array($entity_keys['id'], $entity_keys['revision']),
-        );
-        $other_fields_tables = array('base_table', 'revision_table');
-      }
-      elseif (isset($tables['data_table']) && !isset($tables['revision_table'])) {
-        // @todo Remove this when https://drupal.org/node/2143729 has landed
-        $entity_keys['langcode'] = 'langcode';
-
-        // For translatable, non-revisionable entities the entity key fields
-        // except for ID and language code are only stored in the base table. All
-        // other fields are only stored in the data table. The ID is stored in
-        // both the base table and the data table and the language code is only
-        // stored in the data table. Additionally, whether or not a language
-        // variant belongs to the default language code of an entity is tracked in
-        // the data table as the default language code field and the respective
-        // default language code is stored as the language code field in the base
-        // table.
-        $field_table_mapping = array(
-          'base_table' => array_values($entity_keys),
-          'data_table' => array($entity_keys['id'], 'langcode', 'default_langcode'),
-        );
-        $other_fields_tables = array('data_table');
-      }
-      else {
-        // @todo Remove this when https://drupal.org/node/2143729 has landed
-        $entity_keys['langcode'] = 'langcode';
-
-        // For translatable, revisionable entities the entity key fields except
-        // for ID, language code and revision ID are only stored on the base
-        // table. The ID is stored on the base table, the data table, the revision
-        // table, and the revision data table. The language code is stored both on
-        // the data table and the revision data table. Additionally, whether or
-        // not a language variant belongs to the default language code of an
-        // entity is tracked in the data table as the default language code field
-        // and the respective default language code is stored as the language code
-        // field in the base table. Similarly, whether or not a language variant
-        // belongs to the default language code of an entity revision is tracked
-        // in the revision data table as the default language code field and the
-        // respective default language code is stored as the language code field
-        // in the revision table. Furthermore, the revision ID is stored both in
-        // the revision table and the revision data table. Additionally, the
-        // default revision ID of an entity is tracked as the revision ID field in
-        // both the base table and the data table. Other fields are stored in the
-        // revision data table and other fields of the default revision are stored
-        // in the data table.
-        $field_table_mapping = array(
-          'base_table' => array_values($entity_keys),
-          'revision_table' => array($entity_keys['id'], $entity_keys['revision'], 'langcode'),
-          'data_table' => array($entity_keys['id'], $entity_keys['revision'], 'langcode', 'default_langcode'),
-          'revision_data_table' => array($entity_keys['id'], $entity_keys['revision'], 'langcode', 'default_langcode'),
-        );
-        $other_fields_tables = array('data_table', 'revision_data_table');
+      if ($this->dataTable) {
+        $entity_keys['language'] = 'langcode';
+        $entity_keys['default_language'] = 'default_langcode';
       }
 
       // Add primary keys and common foreign keys to the tables.
       $this->schema[$tables['base_table']]['primary key'] = array($entity_keys['id']);
       $this->schema[$tables['base_table']]['foreign keys'] = array();
-      if (isset($tables['data_table'])) {
-        $this->schema[$tables['data_table']]['primary key'] = array($entity_keys['id'], 'langcode');
-        $this->schema[$tables['data_table']]['foreign keys'][$entity_keys['id']] = array(
+      if (isset($tables['revision_table'])) {
+        $this->schema[$tables['revision_table']]['primary key'] = array($entity_keys['revision']);
+        $this->schema[$tables['revision_table']]['foreign keys'][$entity_keys['id']] = array(
           'table' => $tables['base_table'],
           'columns' => array($entity_keys['id'] => $entity_keys['id']),
         );
       }
-      if (isset($tables['revision_table'])) {
-        $this->schema[$tables['revision_table']]['primary key'] = array($entity_keys['revision']);
-        $this->schema[$tables['revision_table']]['foreign keys'][$entity_keys['id']] = array(
+      if (isset($tables['data_table'])) {
+        $this->schema[$tables['data_table']]['primary key'] = array($entity_keys['id'], 'langcode');
+        $this->schema[$tables['data_table']]['foreign keys'][$entity_keys['id']] = array(
           'table' => $tables['base_table'],
           'columns' => array($entity_keys['id'] => $entity_keys['id']),
         );
@@ -1636,60 +1567,35 @@ public function getSchema($table_key = NULL) {
       // info or alter hooks.
       foreach($class::baseFieldDefinitions($entity_type_id) as $field_name => $field_definition) {
         /** @var \Drupal\Core\Field\FieldDefinitionInterface $field_definition */
+        if ($field_definition->isComputed()) {
+          continue;
+        }
 
-        $field_schema = $field_definition->getSchema();
-        $field_schema['description'] = $field_definition->getDescription();
-
-        $single_column_field = count($field_schema['columns']) == 1;
-        $main_property_name = $field_definition->getMainPropertyName();
-
-        if (in_array($field_name, $entity_keys)) {
-          foreach ($field_table_mapping as $table_key => $field_names) {
-            if (in_array($field_name, $field_names)) {
-              if (!$single_column_field) {
-                throw new \LogicException("The $field_name field of the $entity_type_id entity type has multiple columns.");
-              }
-              $this->schema[$tables[$table_key]]['fields'][$field_name] = $field_schema['columns'][$main_property_name];
-              $this->schema[$tables[$table_key]]['fields'][$field_name]['description'] = $field_definition->getDescription();
-
-              if (!empty($field_schema['unique keys'])) {
-                $this->schema[$tables[$table_key]]['unique keys'][$field_name] = array($field_name);
-              }
-              if (!empty($field_schema['indexes'])) {
-                // @todo Support indexes specified as an array of column name and
-                //   length.
-                $this->schema[$tables[$table_key]]['indexes'][$field_name] = array($field_name);
-              }
-              if (!empty($field_schema['foreign keys'])) {
-                $this->schema[$tables[$table_key]]['foreign keys'] += $field_schema['foreign keys'];
-              }
-            }
+        if (FALSE !== $key = array_search($field_name, $entity_keys)) {
+          if ($key !== 'default_language') {
+            $this->addFieldSchema($this->schema[$this->baseTable], $field_name, $field_definition);
+          }
+          if ($this->revisionTable && in_array($key, array('id', 'revision', 'language'))) {
+            $this->addFieldSchema($this->schema[$this->revisionTable], $field_name, $field_definition);
+          }
+          if ($this->dataTable && in_array($key, array('id', 'revision', 'language', 'default_language'))) {
+            $this->addFieldSchema($this->schema[$this->dataTable], $field_name, $field_definition);
+          }
+          if ($this->revisionDataTable && in_array($key, array('id', 'revision', 'language', 'default_language'))) {
+            $this->addFieldSchema($this->schema[$this->revisionDataTable], $field_name, $field_definition);
           }
         }
         else {
-          foreach ($other_fields_tables as $table_key) {
-            if ($single_column_field) {
-              $this->schema[$tables[$table_key]]['fields'][$field_name] = $field_schema['columns'][$main_property_name];
-              $this->schema[$tables[$table_key]]['fields'][$field_name]['description'] = $field_definition->getDescription();
-
-              if (!empty($field_schema['unique keys'])) {
-                $this->schema[$tables[$table_key]]['unique keys'][$field_name] = array($field_name);
-              }
-              if (!empty($field_schema['indexes'])) {
-                // @todo Support indexes specified as an array of column name and
-                //   length.
-                $this->schema[$tables[$table_key]]['indexes'][$field_name] = array($field_name);
-              }
-              if (!empty($field_schema['foreign keys'])) {
-                $this->schema[$tables[$table_key]]['foreign keys'] += $field_schema['foreign keys'];
-              }
+          if (!$this->dataTable || !$field_definition->isTranslatable()) {
+            $this->addFieldSchema($this->schema[$this->baseTable], $field_name, $field_definition);
+            if ($this->revisionTable) {
+              $this->addFieldSchema($this->schema[$this->revisionTable], $field_name, $field_definition);
             }
-            else {
-              foreach ($field_schema['columns'] as $column_name => $column_schema) {
-                $this->schema[$tables[$table_key]]['fields'][$field_name . '__' . $column_name] = $column_schema;
-              }
-
-              // @todo Unique keys, indexes and foreign keys.
+          }
+          else {
+            $this->addFieldSchema($this->schema[$this->dataTable], $field_name, $field_definition);
+            if ($this->revisionDataTable) {
+              $this->addFieldSchema($this->schema[$this->revisionDataTable], $field_name, $field_definition);
             }
           }
         }
@@ -1724,6 +1630,43 @@ public function getSchema($table_key = NULL) {
   }
 
   /**
+   * Adds the schema for a single to the table schema.
+   *
+   * @param array $schema
+   *   The schema array for a table, passed by reference.
+   * @param string $field_name
+   *   The name of the field.
+   * @param \Drupal\Core\Field\FieldDefinitionInterface $field_definition
+   *   The field definition of the field.
+   */
+  protected function addFieldSchema(&$schema, $field_name, FieldDefinitionInterface $field_definition) {
+    $field_schema = $field_definition->getSchema();
+    if (count($field_schema['columns']) == 1) {
+      $schema['fields'][$field_name] = $field_schema['columns'][$field_definition->getMainPropertyName()];
+      $schema['fields'][$field_name]['description'] = $field_definition->getDescription();
+
+      if (!empty($field_schema['unique keys'])) {
+        $schema['unique keys'][$field_name] = array($field_name);
+      }
+      if (!empty($field_schema['indexes'])) {
+        // @todo Support indexes specified as an array of column name and
+        //   length.
+        $schema['indexes'][$field_name] = array($field_name);
+      }
+      if (!empty($field_schema['foreign keys'])) {
+        $schema['foreign keys'] += $field_schema['foreign keys'];
+      }
+    }
+    else {
+      foreach ($field_schema['columns'] as $column_name => $column_schema) {
+        $schema['fields'][$field_name . '__' . $column_name] = $column_schema;
+      }
+
+      // @todo Descriptions, unique keys, indexes and foreign keys.
+    }
+  }
+
+  /**
    * Checks whether the entity tables exist in the database.
    *
    * @return bool
diff --git a/core/modules/taxonomy/lib/Drupal/taxonomy/Entity/Term.php b/core/modules/taxonomy/lib/Drupal/taxonomy/Entity/Term.php
index e366b85..3c4198f 100644
--- a/core/modules/taxonomy/lib/Drupal/taxonomy/Entity/Term.php
+++ b/core/modules/taxonomy/lib/Drupal/taxonomy/Entity/Term.php
@@ -240,7 +240,10 @@ public static function baseFieldDefinitions($entity_type) {
       ->setDescription(t('The parents of this term.'))
       // Save new terms with no parents by default.
       ->setSetting('default_value', 0)
-      ->setConstraints(array('TermParent' => array()));
+      ->setConstraints(array('TermParent' => array()))
+      // The parent of a taxonomy term is not computed from other fields but is
+      // stored separately in the {taxonomy_term_hierarchy] table.
+      ->setComputed(TRUE);
 
     $fields['changed'] = FieldDefinition::create('integer')
       ->setLabel(t('Changed'))
diff --git a/core/modules/user/lib/Drupal/user/Entity/User.php b/core/modules/user/lib/Drupal/user/Entity/User.php
index 44bce77..02a0bce 100644
--- a/core/modules/user/lib/Drupal/user/Entity/User.php
+++ b/core/modules/user/lib/Drupal/user/Entity/User.php
@@ -513,7 +513,10 @@ public static function baseFieldDefinitions($entity_type) {
     // https://drupal.org/node/2044859.
     $fields['roles'] = FieldDefinition::create('string')
       ->setLabel(t('Roles'))
-      ->setDescription(t('The roles the user has.'));
+      ->setDescription(t('The roles the user has.'))
+      // The roles of a user are not computed from other fields but are stored
+      // separately in the {users_roles} table.
+      ->setComputed(TRUE);
 
     return $fields;
   }