还是sql问题，两次调用自定义function结果如何求和？
我这儿有个大sql如下，逻辑倒也简单

SQL code

select case         when '1' = '1' and '2011-05-29' is not null and         (calInteval(to_date('2009-09-28', 'yyyy-mm-dd'),to_date('2011-05-29', 'yyyy-mm-dd')) <= 180 or         (calInteval(to_date('2010-12-01', 'yyyy-mm-dd'),to_date('2011-05-29', 'yyyy-mm-dd')) > 0 and           calInteval(to_date('2010-12-01', 'yyyy-mm-dd'),to_date('2011-05-29', 'yyyy-mm-dd')) <= 180)) then          (select GETSUMSTANDMONEY('2009002993778021', date'2011-05-29') from LDSysVar where SysVar = 'onerow' +            select GETSUMSTANDMONEY('2009002993779021', date'2011-05-29') from LDSysVar where SysVar = 'onerow'          )        else          0       endfrom dual

其中这两行代码

SQL code

select GETSUMSTANDMONEY('2009002993778021', date'2011-05-29') from LDSysVar where SysVar = 'onerow' +            select GETSUMSTANDMONEY('2009002993779021', date'2011-05-29') from LDSysVar where SysVar = 'onerow'

GETSUMSTANDMONEY 是个自定义的function ，单独执行每一条语句都可以得到结果，而且返回值是number型的，
但是那样加起来就报错。大侠们帮看看。

[解决办法]
多加两重括号试试看？

((select GETSUMSTANDMONEY('2009002993778021', date'2011-05-29') from LDSysVar where SysVar = 'onerow') + (select GETSUMSTANDMONEY('2009002993779021', date'2011-05-29') from LDSysVar where SysVar = 'onerow'))