数据库每日一练01

部门月份业绩表

CREATE TABLE [dbo].[bmy](
 [mon] [varchar](50) COLLATE Chinese_PRC_CI_AS NULL,
 [dep] [varchar](18) COLLATE Chinese_PRC_CI_AS NULL,
 [yj] [numeric](18, 0) NULL,
 [id] [int] NOT NULL,
PRIMARY KEY CLUSTERED
(
 [id] ASC
)WITH (IGNORE_DUP_KEY = OFF) ON [PRIMARY]
) ON [PRIMARY]
 

部门表

CREATE TABLE [dbo].[depart](
 [dep] [varchar](50) COLLATE Chinese_PRC_CI_AS NULL,
 [dname] [nchar](10) COLLATE Chinese_PRC_CI_AS NULL
) ON [PRIMARY]

数据统计：

--统计每个部门的每个月份业绩
select  depart.dname dep,sum(case when bmy.mon ='一月份' then bmy.yj else null end) as 一月份,
    sum(case when bmy.mon ='二月份' then bmy.yj else null end)  as 二月份,
    sum(case when bmy.mon ='三月份' then bmy.yj else null  end) as 三月份
from  bmy
left join  depart on  bmy.dep = depart.dep
group by depart.dname
order by depart.dname

--统计在bmy中，存在多个月份记录的月份，和次数
select  mon ,count(*) num from  bmy group by mon having  count(*) > 1
select  *   from( select  mon ,count(*) as num from bmy group by  mon )t where t.num > 1