--兩個截然不同
select
isnull(max(ti_goods_count)-
sum(isnull(sl_count,0)),0) as ti_goods_count, isnull(max(ti_goods_weight)-
sum(isnull(sl_weight,0)),0) as ti_goods_weight, isnull(max(ti_goods_body)-
sum(isnull(sl_body,0)),0) as ti_goods_body, isnull(max(ti_prepay_price)-
sum(isnull(sl_prepay_price,0)),0) as ti_prepay_price, isnull(max(ti_return_price)-
sum(isnull(sl_return_price,0)),0) as ti_return_price, isnull(max(ti_arrive_price)-
sum(isnull(sl_arrive_price,0)),0) as ti_arrive_price, isnull(max(ti_month_price)-
sum(isnull(sl_month_price,0)),0) as ti_month_price, isnull(max(ti_sum_price)-
sum(isnull(sl_sum_price,0)),0) as ti_sum_price, isnull(max(ti_back_is_price)-
sum(isnull(sl_isback,0)),0) as ti_back_is_price, isnull(max(ti_back_isnot_price)-
sum(isnull(sl_notback,0)),0) as
ti_back_isnot_price,
isnull(max(ti_back_price)-
sum(isnull(sl_back_price,0)),0) as
ti_back_price
from t_send_list right
join t_ticket_info on ti_id = sl_ti_id where sl_ti_id=
2317
--------------------------------
select
isnull(max(ti_goods_count)-
sum(isnull(sl_count,0)),0) as ti_goods_count, isnull(max(ti_goods_weight)-
sum(isnull(sl_weight,0)),0) as ti_goods_weight, isnull(max(ti_goods_body)-
sum(isnull(sl_body,0)),0) as ti_goods_body, isnull(max(ti_prepay_price)-
sum(isnull(sl_prepay_price,0)),0) as ti_prepay_price, isnull(max(ti_return_price)-
sum(isnull(sl_return_price,0)),0) as ti_return_price, isnull(max(ti_arrive_price)-
sum(isnull(sl_arrive_price,0)),0) as ti_arrive_price, isnull(max(ti_month_price)-
sum(isnull(sl_month_price,0)),0) as ti_month_price, isnull(max(ti_sum_price)-
sum(isnull(sl_sum_price,0)),0) as ti_sum_price, isnull(max(ti_back_is_price)-
sum(isnull(sl_isback,0)),0) as ti_back_is_price, isnull(max(ti_back_isnot_price)-
sum(isnull(sl_notback,0)),0) as
ti_back_isnot_price,
isnull(max(ti_back_price)-
sum(isnull(sl_back_price,0)),0) as
ti_back_price
from t_send_list right
join t_ticket_info on ti_id = sl_ti_id where ti_id=
2317
如果未作發貨則，第一條語句會有資料，第二條將沒有資料，雖然是相同的意思ti_id等同於sl_ti_id,但外來鍵為空時就有意外了。！！
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