sql 查询一行内几列的平均值,最大值,最小值,怎么写比如 name 1 2 6 7 9 0 3 求 1,2,6,7,9,0,3这几个值的最大最小平均值
问题描述:
sql 查询一行内几列的平均值,最大值,最小值,怎么写
比如 name 1 2 6 7 9 0 3
求 1,2,6,7,9,0,3这几个值的最大最小平均值
答
oracle的话直接用greatest函数,sql server的话照这么写:
select t1.name,max(t1.a) maxnum,min(t1.a) minnum,avg(t1.a) avgnum from
(select name,num1 a from tb1
union all
select name,num2 a from tb1
union all
select name,num3 a from tb1
union all
select name,num4 a from tb1
union all
select name,num5 a from tb1
union all
select name,num6 a from tb1
union all
select name,num7 a from tb1) t1
group by t1.name;
测试数据:
create table tb1(name varchar(50),num1 int,num2 int,num3 int,num4 int,num5 int,num6 int,num7 int)
insert into tb1 select 'Tom',1,2,6,7,9,0,3
insert into tb1 select 'Jacky',7,6,5,4,3,2,1
结果:
name maxnum minnum avgnum
Jacky 7 1 4
Tom 9 0 4