TextLongItem.php

<?php

namespace Drupal\text\Plugin\Field\FieldType;

use Drupal\Core\Field\Attribute\FieldType;
use Drupal\Core\Field\FieldStorageDefinitionInterface;
use Drupal\Core\StringTranslation\TranslatableMarkup;

/**
 * Plugin implementation of the 'text_long' field type.
 */
class TextLongItem extends TextItemBase {
  
  /**
   * {@inheritdoc}
   */
  public static function schema(FieldStorageDefinitionInterface $field_definition) {
    return [
      'columns' => [
        'value' => [
          'type' => 'text',
          'size' => 'big',
        ],
        'format' => [
          'type' => 'varchar_ascii',
          'length' => 255,
        ],
      ],
      'indexes' => [
        'format' => [
          'format',
        ],
      ],
    ];
  }

}