UniqueKey

class \Drupal\Core\Database\SchemaDefinition\KeyBase implements \Drupal\Core\Database\SchemaDefinition\SchemaDefinitionInterface
- class \Drupal\Core\Database\SchemaDefinition\ForeignKey extends \Drupal\Core\Database\SchemaDefinition\KeyBase
- class \Drupal\Core\Database\SchemaDefinition\Index extends \Drupal\Core\Database\SchemaDefinition\KeyBase
- class \Drupal\Core\Database\SchemaDefinition\PrimaryKey extends \Drupal\Core\Database\SchemaDefinition\KeyBase
- class \Drupal\Core\Database\SchemaDefinition\UniqueKey extends \Drupal\Core\Database\SchemaDefinition\KeyBase

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