Mysql中實現行轉列或者實現以下操作的實現:
使用max()函數與case......when........then.......else......end實現
eg: 表A select year ,
max(case month when '1' then amount else 0 end ) m1,
max(case month when '2' then amount else 0 end )m2,
max(case month when '3' then amount else 0 end ) m3
from A group by year
oracle中行轉列的實現
SELECT a.* FROM A a pivot(MAX(a.amount) FOR month IN ('1','2','3'))a