经典sql总结(2)
如何做呢，跟上文区别不大。
我建个表，输入以下
1 select year, 2 (select amount from info2 as t2 where t2.year=t.year and t2.mouth=1) as m1, 3 (select amount from info2 as t3 where t3.year=t.year and t3.mouth=2) as m2, 4 (select amount from info2 as t4 where t4.year=t.year and t4.mouth=3) as m3 5 from info2 as t group by year;
