Function SPI_register_relation

src/backend/executor/spi.c:3560–3588

* Register an ephemeral named relation for use by the planner and executor on * subsequent calls using this SPI connection. */

 * subsequent calls using this SPI connection.
 */
int
SPI_register_relation(EphemeralNamedRelation enr)
{
	EphemeralNamedRelation match;
	int			res;

	if (enr == NULL || enr->md.name == NULL)
		return SPI_ERROR_ARGUMENT;

	res = _SPI_begin_call(false);	/* keep current memory context */
	if (res < 0)
		return res;

	match = _SPI_find_ENR_by_name(enr->md.name);
	if (match)
		res = SPI_ERROR_REL_DUPLICATE;
	else
	{
		if (_SPI_current->queryEnv == NULL)
			_SPI_current->queryEnv = create_queryEnv();

		register_ENR(_SPI_current->queryEnv, enr);
		res = SPI_OK_REL_REGISTER;
	}

	_SPI_end_call(false);

	return res;
}

/*
 * Unregister an ephemeral named relation by name.  This will probably be a