------------------case---when-------的使用---------------------
select userAccount , eatingDate ,
case when sum(a)=1 then'早餐' else '' end as 'breakfast' ,
case when sum(b)=1 then '午餐' else '' end as 'lunch',
case when sum(c)=1 then '晚餐' else '' end as 'dinner'
from (
select userAccount , eatingDate ,
case when menuType='早餐' then 1 else 0 end AS a ,
case when menuType='午餐' then 1 else 0 end AS b ,
case when menuType='晚餐' then 1 else 0 end AS c
from view_menuReservation
where userAccount = '7923'
and eatingDate between '2016-12-01' and'2016-12-31'
) t
group by userAccount ,eatingDate
order by eatingDate asc
---------------------查询的时候嵌套子查询-----------------------------------------
SELECT tb.account, '2016-10' month,
( max(CASE signStatus WHEN '准时' THEN total ELSE 0 END )+
max(CASE signStatus WHEN '调休' THEN total ELSE 0 END)+
max(CASE signStatus WHEN '迟到' THEN total ELSE 0 END)
) sumDay,
(max(CASE signStatus WHEN '准时' THEN total ELSE 0 END)
+ max(CASE signStatus WHEN '调休' THEN total ELSE 0 END)) onTime,
max(CASE signStatus WHEN '迟到' THEN total ELSE 0 END) late,
max(CASE signStatus WHEN '请假' THEN total ELSE 0 END) leave,
max(CASE signStatus WHEN '早退' THEN total ELSE 0 END) absenteeism,
( select count(*) from tb_workAttendance
where workStatus='加班' and
docdate between '2016-10-1' and '2016-10-31' and account = tb.account and signType='上班' group by workStatus) overtime,
0 dayOff,
(select sum (totalHour) totalHour from tb_restApply where docdate between '2016-11-01' and '2016-11-30' and account=tb.account group by account) totalHour
from(
select count(1) total, signStatus, account
from tb_workAttendance
where docdate between '2016-10-1' and '2016-10-31'
group by signStatus,account)
tb
group by account
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