不知道错在哪儿 帮忙！！

Question

select (case a.shipduty_Id when in (select shipduty_Id from ShipyardProjectinfo) then ShipyardProjectinfo.ProjectInfo else 0 end) ProjectInfo,a.shipduty_id,a.inputtime,a.disposeType,a.defendOfficeOperate,b.ShipSerial,b.ship_Id from Workshipduty a,shipinfo b where a.ship_Id=b.ship_id and a.disposeType>3 order by a.shipduty_id desc

Answer 1

(case a.shipduty_Id when in (select * from ShipyardProjectinfo) then ShipyardProjectinfo.ProjectInfo else 0 end) 有问题。
改一下：
select nvl(c.shipduty_Id), ProjectInfo,a.shipduty_id,a.inputtime,a.disposeType,
a.defendOfficeOperate,b.ShipSerial,b.ship_Id 
from Workshipduty a,shipinfo b，（select shipduty_Id when in (select * from ShipyardProjectinfo))c
where a.ship_Id=b.ship_id and a.disposeType>3 and a.shipduty_Id=c.shipduty_Id(+)
order by a.shipduty_id desc

Answer 2

sorry:
select nvl(c.shipduty_Id,0), ProjectInfo,a.shipduty_id,a.inputtime,a.disposeType,
a.defendOfficeOperate,b.ShipSerial,b.ship_Id 
from Workshipduty a,shipinfo b，
（select shipduty_Id when in (select * from ShipyardProjectinfo))c
where a.ship_Id=b.ship_id and a.disposeType>3 
and a.shipduty_Id=c.shipduty_Id(+)
order by a.shipduty_id desc