select parse_url('http://facebook.com/path/p1.php?query=1', 'HOST') from dw.d_city limit 1; ---- facebook.com
select parse_url('http://facebook.com/path/p1.php?query=1', 'PATH') from dw.d_city limit 1; ---- /path/p1.php
select parse_url('http://facebook.com/path/p1.php?query=1', 'QUERY') from dw.d_city limit 1;----query=1
select parse_url('http://facebook.com/path/p1.php?query=1&name=3', 'QUERY','query')
from dw.d_city limit 1;------ 1
select parse_url('http://facebook.com/path/p1.php?query=1&name=3', 'QUERY','name')
from dw.d_city limit 1;---- 3
select parse_url('http://facebook.com/path/p1.php?query=1', 'REF') from dw.d_city limit 1; ---- 空
select parse_url('http://facebook.com/path/p1.php?query=1', 'PROTOCOL') from dw.d_city limit 1;---- http
select parse_url('http://facebook.com/path/p1.php?query=1', 'FILE') from dw.d_city limit 1;----/path/p1.php?query=1
select parse_url('http://facebook.com/path/p1.php?query=1', 'AUTHORITY') from dw.d_city limit 1;----facebook.com
select parse_url('http://facebook.com/path/p1.php?query=1', 'USERINFO') from dw.d_city limit 1;----空