select sua.id, loc_h.id loc_host_id, loc_h.host_name loc_host, sua.user_agent, inet_ntoa(sua.last_ip) ip, sua.confirm, 
min(sr.t) _min, max(sr.t) _max, count(sr.agent) count, ref_p.uri referer, ref_h.host_name, ref_p.id idsp
   	from stat_requests sr
   	join stat_user_agents sua on sr.agent=sua.id  
   	left join stat_pages ref_p on ref_p.id=sua.referer
   	left join stat_hosts ref_h on ref_p.host=ref_h.id	
   	join stat_pages loc_p on loc_p.id=sr.page
   	join stat_hosts loc_h on loc_p.host=loc_h.id
   	group by sr.agent
   	order by _max desc limit 100
 

id select_type 	table 	type 	possible_keys 	key 	key_len 	ref 	rows 	Extra 	
1 	SIMPLE 	sua 	ALL 	PRIMARY 	NULL	NULL	NULL	240590 	Using temporary; Using filesort
1 	SIMPLE 	ref_p 	eq_ref 	PRIMARY 	PRIMARY 	4 	stat.sua.referer 	1 	
1 	SIMPLE 	ref_h 	eq_ref 	PRIMARY 	PRIMARY 	4 	stat.ref_p.host 	1 	
1 	SIMPLE 	sr 	ref 	agent 	agent 	4 	stat.sua.id 	8 	
1 	SIMPLE 	loc_p 	eq_ref 	PRIMARY,urii,host 	PRIMARY 	4 	stat.sr.page 	1 	Using where
1 	SIMPLE 	loc_h 	eq_ref 	PRIMARY 	PRIMARY 	4 	stat.loc_p.host 	1 	

SELECT sr.agent, min( sr.t ) _min, max( sr.t ) _max, count( sr.agent ) _count
FROM stat_requests sr
JOIN stat_user_agents sua ON sr.agent = sua.id
GROUP BY sr.agent
ORDER BY _max DESC
LIMIT 100 

id 	select_type 	table 	type 	possible_keys 	key 	key_len 	ref 	rows 	Extra 	
1 	SIMPLE 	sr 	ALL 	agent 	NULL	NULL	NULL	1874360 	Using temporary; Using filesort
1 	SIMPLE 	sua 	eq_ref 	PRIMARY 	PRIMARY 	4 	stat.sr.agent 	1 	Using index