关于SQL语句优化的问题

[还在查]

select * from ZS_PrimDatatb where OccurDate='20130901' and SiteNo ='10001' and ZHMODICHECKWORKER is null and tradenumber in(select tradenumber from zs_scanlogtb where scansource='1') and (BillCheckFlag<>9 and MBillCheckFlag<>9 and CheckFlag<>9 and MCheckFlag<>9) order by TradeNumber

这个SQL语句有没有更好的写法或者索引来提高效率？

[buyong]

见联合索引 OccurDate，SiteNo ZHMODICHECKWORKER tradenumber BillCheckFlag MBillCheckFlag CheckFlag MCheckFlag

[TUBER727]

用EXISTS替代IN可以提高查询的效率