我想实现数据的更新,请问下面的sql怎么改才行啊?
update BUS_PROD_ITEM_SN b set b.ACTION_BY =
(select t.ACTION_BY from BUS_PROD_SN_LOG t
where t.PRODUCT_ITEM_SN_IDX = b.prod_item_sn_idx and rownum<=1 order by t.prod_sn_log_idx desc)
update BUS_PROD_ITEM_SN b set b.ACTION_BY =
(select t.ACTION_BY from BUS_PROD_SN_LOG t
where t.PRODUCT_ITEM_SN_IDX = b.prod_item_sn_idx and rownum<=1 order by t.prod_sn_log_idx desc)
(select ACTION_BY from
select ACTION_BY from BUS_PROD_SN_LOG t
where t.PRODUCT_ITEM_SN_IDX = b.prod_item_sn_idx order by t.prod_sn_log_idx desc) where rownum<=1;
(select ACTION_BY from
select ACTION_BY from BUS_PROD_SN_LOG t
where t.PRODUCT_ITEM_SN_IDX = b.prod_item_sn_idx order by t.prod_sn_log_idx desc) where rownum<=1);最后少了一)。