Connection::__construct

public Connection::__construct(\PDO $connection, array $connection_options)

public function __construct(\PDO $connection, array $connection_options) {
  parent::__construct($connection, $connection_options);

  // This driver defaults to transaction support, except if explicitly passed FALSE.
  $this->transactionSupport = !isset($connection_options['transactions']) || ($connection_options['transactions'] !== FALSE);

  // Transactional DDL is always available in PostgreSQL,
  // but we'll only enable it if standard transactions are.
  $this->transactionalDDLSupport = $this->transactionSupport;

  $this->connectionOptions = $connection_options;

  // Force PostgreSQL to use the UTF-8 character set by default.
  $this->connection->exec("SET NAMES 'UTF8'");

  // Execute PostgreSQL init_commands.
  if (isset($connection_options['init_commands'])) {
    $this->connection->exec(implode('; ', $connection_options['init_commands']));
  }
}