If on "accident" your program passes pg_result_status a variable that is NOT a actual pg resource, it will return an empty string.
(This is important to know if you want to make sure a pg resource is "good" before attempting some operation on it).
pg_result_status
说明
int pg_result_status ( resource result )pg_result_status() 返回该查询结果资源的状态。可能的返回值有 PGSQL_EMPTY_QUERY，PGSQL_COMMAND_OK，PGSQL_TUPLES_OK，PGSQL_COPY_TO，PGSQL_COPY_FROM，PGSQL_BAD_RESPONSE，PGSQL_NONFATAL_ERROR 和 PGSQL_FATAL_ERROR。
add a note
User Contributed Notes
Meej Vaj
09-Jun-2005 09:45
09-Jun-2005 09:45
romix at gmx dot de
16-Oct-2002 09:29
16-Oct-2002 09:29
0 = PGSQL_EMPTY_QUERY
1 = PGSQL_COMMAND_OK
2 = PGSQL_TUPLES_OK
3 = PGSQL_COPY_TO
4 = PGSQL_COPY_FROM
5 = PGSQL_BAD_RESPONSE
6 = PGSQL_NONFATAL_ERROR
7 = PGSQL_FATAL_ERROR