如果数值不匹配，我如何计数记录并中断？

Question

我有这个表中的记录

No | Part | value | 
------ | ------|------ | 
    1 | A1 | 2 | 
    2 | A1 | 2 | 
    3 | A1 | 1 | 
    4 | A1 | 2 | 
    5 | A1 | 2 | 
    6 | A1 | 2 | 

我能指望最后一个记录和休息/结束算起值不匹配？

例如计数值等于2，计数结果为3

Answer 1

我怀疑你的意思是相邻值的计数是相同的。在SQL Server 2005中，您可以使用行号的差异来执行此操作：

select count(*) 
from (select value, (seqnum - seqnum_v), grp, count(*) as cnt 
     from (select t.*, 
        row_number() over (partition by part order by id) as seqnum, 
        row_number() over (partition by part, value order by id) as seqnum_v 
      from t 
      ) t 
     group by value, (seqnum - seqnum_v) 
    ) t;