SQL:两表查询和删除，这么写有问题吗？
有两个表，一个订单表tborder，另一个订单详细表tbitem
订单表tborder主键为order_id，订单详细表tbitem的主键为order_id+item_id。
现发现订单表中有的order_id没有出现在订单详细表中。
为了整合数据，要把这些order_id找出来并删除。
SELEC * FROM tborder a WHERE a.order_id not in (SELECT b.order_id FROM tbitem b)
DELETE FROM tborder a WHERE a.order_id not in (SELECT b.order_id FROM tbitem b)
这两条SQL语句有什么问题吗？还有什么更好的SQL吗？
望指教。。
[解决办法]
SELEC * FROM tborder a WHERE not exists(
SELECT top(1)1 from tbitem b where a.order_id=b.order_id
)
DELETE FROM tborder a WHERE not exists(
SELECT top(1)1 from tbitem b where a.order_id=b.order_id
)
--查询
SELECT *
FROM tborder
WHERE order_id not in (SELECT order_id FROM tbitem)
--删除
DELETE FROM tborder
WHERE order_id not in (SELECT order_id FROM tbitem)
或者：
SELECT *
FROM tborder a
WHERE not exists(SELECT 1 FROM tbitem b where a.order_id=b.order_id)
DELETE FROM tborder a
WHERE not exists(SELECT 1 FROM tbitem b where a.order_id=b.order_id)
