elect dd.eday as'日期',if(tp.c is null, 0, tp.c)as '访问量' from (

select 1 as eday union select 2 union select 3 union select 4 union select 5 

              union select 6 union select 7 union select 8 union select 9 union select 10 

              union select 11 union select 12 union select 13 union select 14 union select 15 

              union select 16 union select 17 union select 18 union select 19 union select 20 

              union select 21 union select 22 union select 23 union select 24 union select 25 

              union select 26 union select 27 union select 28 union select 29 union select 30 

              union select 31) dd

left join (

select DATE_FORMAT(rf.client_datetime, '%e') d , DATE_FORMAT(rf.client_datetime, '%Y%m%d')s, COUNT(*) c from  api_flow_jnl rf

where rf.client_datetime>'2014-05-01' 

and rf.client_datetime<'2014-05-31'

group by d) tp 

on tp.d = dd.eday;