SQL

Question

我有一个 table 具有以下值：

如果具有相同 ID 的值总和 = 0，我想将它们从 table 中删除。所以结果应该是这样的：

我的代码：

DELETE FROM tmp_table
WHERE ID in 
            (SELECT ID
            FROM tmp_table WITH(NOLOCK) 
            GROUP BY ID
            HAVING SUM(value) = 0)

只删除 ID = 2 的行。

UPD：包括附加示例：需要删除黄色行

Answer 1

您的查询工作正常，因为唯一总计为零的组是 id 2，其他组的子组总计为零（例如前两个 id 1）但是所有这些记录的总数是 -3。

你想要的是一个更复杂的算法来执行“bin packing”以删除总和为零的子组。

Answer 2

您可以使用 window 函数做您想做的事——通过枚举每个 id 的值。使用子查询采用您的方法：

with t as (
      select t.*,
             row_number() over (partition by id, value order by id) as seqnum
      from tmp_table t
     )
delete from t
    where exists (select 1
                  from t t2
                  where t2.id = t.id and t2.value = - t.value and t2.seqnum = t.seqnum
                 );

您还可以使用第二层 window 函数来执行此操作：

with t as (
      select t.*,
             row_number() over (partition by id, value order by id) as seqnum
      from tmp_table t
     ),
     tt as (
      select t.*, count(*) over (partition by id, abs(value), seqnum) as cnt
      from t
     )
delete from tt
    where cnt = 2;

SQL - 删除总和 = 0 的记录

SQL - delete record where sum = 0

sql-server

sql-delete