如何提取这两个联合查询语句的共用条件呢？

[yesjoy]

有问题想请教一下，如果我的两条sql语句中都有相同的一个条件，我是否可以共用呢？
比如下面两句中都有一个条件year='1996：

那么我要合并的时候是否能够只写一次啊，因为我实际项目中这个共用条件比较长，总不能都这样写吧：
select a,b from
(select sum(NUMBER_OF_PERSONS) as a from T_ES_TEACHEXPERIMENT where type='1' and year='1996)t1,
(select sum(USE_HOURS) as b from T_ES_TEACHEXPERIMENT where method in('2','3') and year='1996)t2

把共用条件提取出来但是不能影响查询结果，因为我在组织sql语句的时候想把共用的条件定义为一个变量。谢谢

[冷箫轻笛]

select
sum(case when type='1' then NUMBER_OF_PERSONS else 0 end) as a,
sum(case when method in('2','3') then USE_HOURS else 0 end) as b
from T_ES_TEACHEXPERIMENT
where year='1996'

这样写吧

[dulei115]

select sum(case when type='1' then NUMBER_OF_PERSONS end) as a,
sum(case when method in('2','3') then USE_HOURS end) as b
from T_ES_TEACHEXPERIMENT
where year='1996'

[yesjoy]

hibernate中不支持这种写法：
(case when type='1' then NUMBER_OF_PERSONS else 0 end)

也不支持下面这种 ：
(select sum(NUMBER_OF_PERSONS) as a from T_ES_TEACHEXPERIMENT where type='1' and year='1996)t1

有点郁闷

[xiaoku]

hibernate
这个是什么?

[superman_yc]

select
(case when type='1' then sum(NUMBER_OF_PERSONS) end) as a,
(case when method in('2','3') then sum(USE_HOURS) end) as b
from T_ES_TEACHEXPERIMENT
where year='1996'