Possible retun values are PGSQL_EMPTY_QUERY, PGSQL_COMMAND_OK, PGSQL_TUPLES_OK, PGSQL_COPY_TO, PGSQL_COPY_FROM, PGSQL_BAD_RESPONSE, PGSQL_NONFATAL_ERROR and PGSQL_FATAL_ERROR.
Les valeurs retournée possibles sont PGSQL_EMPTY_QUERY, PGSQL_COMMAND_OK, PGSQL_TUPLES_OK, PGSQL_COPY_TO, PGSQL_COPY_FROM, PGSQL_BAD_RESPONSE, PGSQL_NONFATAL_ERROR et PGSQL_FATAL_ERROR.