SQL Server中Rollup关键字使用技巧

首先创建测试表、添加数据。
create table #t(a int,b int,c int,d int,e int)
insert into #t values(1,2,3,4,5)
insert into #t values(1,2,3,4,6)
insert into #t values(1,2,3,4,7)
insert into #t values(1,2,3,4,8)
insert into #t values(1,3,3,4,5)
insert into #t values(1,3,3,4,6)
insert into #t values(1,3,3,4,8)
insert into #t values(1,3,3,4,7)

insert into #t values(2,2,2,4,5)
insert into #t values(2,2,3,4,6)
insert into #t values(2,2,4,4,7)
insert into #t values(2,2,5,4,8)
insert into #t values(2,3,6,4,5)
insert into #t values(2,3,3,4,6)
insert into #t values(2,3,3,4,8)
insert into #t values(2,3,3,4,7)情况一：只有一个分类汇总列时，只需要一个合计。只需要增加with rollup即可。
select case when grouping(a)=1 then '合计' else cast(a as varchar) end a,
sum(b),sum(c),sum(d),sum(e) from #t group by a with rollup
情况二:有多个分类汇总列，只需要一个合计.增加rollup之后，需要增加判断。
select case when grouping(a)=1 then '合计' else cast(a as varchar) end a,
     b,
sum(c),sum(d),sum(e) from #t 
group by a,b with rollup 
having grouping(b)=0 or grouping(a)=1select case when grouping(a)=1 then '合计' else cast(a as varchar) end a,
     b,
     c,
sum(d),sum(e) from #t 
group by a,b,c with rollup 
having grouping(c)=0 or grouping(a)=1
情况三：有多个分类汇总列，需要全部的小计和合计。
select case when grouping(a)=1 then '合计' else cast(a as varchar) end a,
    case when grouping(b)=1 and grouping(a)=0 then '小计' else cast(b as varchar) end b,
    case when grouping(c)=1 and grouping(b)=0 then '小计' else cast(c as varchar) end c,
sum(d),sum(e) from #t 
group by a,b,c with rollup 
另外一种显示小计的方式
select case when grouping(a)=1 then '合计' 
    when grouping(b)=1 then cast(a as varchar)+'小计'
    else cast(a as varchar) end a,
    case when grouping(b)=0 and grouping(c)=1 
    then cast(b as varchar)+'小计' else cast(b as varchar) end b,
    case when grouping(c)=1 and grouping(b)=0 
    then '' else cast(c as varchar) end c,
sum(d),sum(e) from #t 

group by a,b,c with rollup

情况四：有多个分类汇总列，需要部分的小计和合计
select case when grouping(a)=1 then '合计' else cast(a as varchar) end a,
     b,
    case when grouping(c)=1 and grouping(b)=0 then '小计' else cast(c as varchar) end c,
sum(d),sum(e) from #t 
group by a,b,c with rollup 
having grouping(a)=1 or grouping(b)=0
select case when grouping(a)=1 then '合计' else cast(a as varchar) end a,
    case when grouping(b)=1 and grouping(a)=0 then '小计' else cast(b as varchar) end b,
     c,
sum(d),sum(e) from #t 
group by a,b,c with rollup