NodeStorageSchema.php

<?php

namespace Drupal\node;

use Drupal\Core\Entity\ContentEntityTypeInterface;
use Drupal\Core\Entity\Sql\SqlContentEntityStorageSchema;
use Drupal\Core\Field\FieldStorageDefinitionInterface;

/**
 * Defines the node schema handler.
 */
class NodeStorageSchema extends SqlContentEntityStorageSchema {
    
    /**
     * {@inheritdoc}
     */
    protected function getEntitySchema(ContentEntityTypeInterface $entity_type, $reset = FALSE) {
        $schema = parent::getEntitySchema($entity_type, $reset);
        if ($data_table = $this->storage
            ->getDataTable()) {
            $schema[$data_table]['indexes'] += [
                'node__frontpage' => [
                    'promote',
                    'status',
                    'sticky',
                    'created',
                ],
                'node__title_type' => [
                    'title',
                    [
                        'type',
                        4,
                    ],
                ],
            ];
        }
        return $schema;
    }
    
    /**
     * {@inheritdoc}
     */
    protected function getSharedTableFieldSchema(FieldStorageDefinitionInterface $storage_definition, $table_name, array $column_mapping) {
        $schema = parent::getSharedTableFieldSchema($storage_definition, $table_name, $column_mapping);
        $field_name = $storage_definition->getName();
        if ($table_name == 'node_revision') {
            switch ($field_name) {
                case 'langcode':
                    $this->addSharedTableFieldIndex($storage_definition, $schema, TRUE);
                    break;
                case 'revision_uid':
                    $this->addSharedTableFieldForeignKey($storage_definition, $schema, 'users', 'uid');
                    break;
            }
        }
        if ($table_name == 'node_field_data') {
            switch ($field_name) {
                case 'promote':
                case 'status':
                case 'sticky':
                case 'title':
                    // Improves the performance of the indexes defined
                    // in getEntitySchema().
                    $schema['fields'][$field_name]['not null'] = TRUE;
                    break;
                case 'changed':
                case 'created':
                    // @todo Revisit index definitions:
                    //   https://www.drupal.org/node/2015277.
                    $this->addSharedTableFieldIndex($storage_definition, $schema, TRUE);
                    break;
            }
        }
        return $schema;
    }

}