Question

我是SQL的新手，我遇到了这个。 Here's a screenshot

我的问题是，如果NULL上的所有primary_payer_id只有具有相同的ClientID和ActionCode IS NOT NULL，才能获得上述值。仅供参考CustomColumn只是primary_payer_id的副本，我在下面附上了我的代码。

这是我的代码：

       SELECT ci.client_id AS ClientID,
               ci.primary_payer_id,                         
               ci.effective_date AS EffectiveDate,
               ci.action_code_id AS ActionCode,
               cc.item_description AS ItemDesc,
               ap.description AS IDescription,
               ci.deleted 



        FROM census_item ci

            LEFT JOIN common_code cc ON ci.adt_tofrom_id = cc.item_id
            LEFT JOIN ar_lib_payers ap ON ci.primary_payer_id = ap.payer_id 

        WHERE ci.deleted = 'N'

Answer 1

可能有一种更有效的方法，但这可行：

with t as (
      <your query here>
     )
select t.*,
       (case when t.actioncode is not null and t.clientid is null
             then tprev.clientid
             else t.clientid
        end) as new_clientid
from t outer apply
     (select top 1 tprev.*
      from t tprev
      where tprev.clientid = t.clientid and
            tprev.effectivedate < t.effectivedate
      order by tprev.effecctivedate desc
     ) tprev;

如果row为null，如何从具有相同ID的上一行获取值？

1 个答案: