已知A表,怎么生成B表,用sql语句实现?跪求!!!
table A 三个字段为
id type value
1 1 50
1 1 100
1 2 100
1 2 50
2 1 50
2 1 30
2 2 50
2 2 50
table B
id type1_value type2_value
1 150 150
2 80 100
问题是:已知A表,怎么生成B表,用sql语句实现?
[解决办法]
create table B(id,type1_value,type2_value) as select id,type,value from A;
[解决办法]
insert into b
select id,
sum(if(type=1,value,0)) as type1_value,
sum(if(type=2,value,0)) as type2_value
from A
group by id