Question

尝试制作一个能够计算我所拥有的问题数量并使用正确的WHERE子句

的表格

   create table #test(
    BatchNo int,
    Q varchar(MAX),
    number varchar(MAX),
    DayNo varchar(MAX),
    total int 
   )

  INSERT INTO #test ( BatchNo, Q,number, DayNo, total ) VALUES
  ( 2, 'A','1', '1', NULL ),
  ( 2, 'A','1', '1', NULL ),
  ( 8, 'A','3', '1', NULL ),
  ( 8, 'A','3', '1', NULL ),
  ( 99, 'A','4', '1', NULL ),
  ( 200, 'A','3', '1', NULL ),
  ( 200, 'A','3', '1', NULL ),
  ( 200, 'A','3', '1', NULL )

我使用了这个UPDATE因为某些原因GROUP BY Batchno不能使用UPDATE

UPDATE #test set total= (select count(batchno)as total from #test where (number=1 or number=3) and DayNo=1)

select * from #test
drop table #test

我不断得到这个结果

  batchno | Q | number | DayNo | total
   2        A     1      1        7
   2        A     1      1        7
   8        A     3      1        7
   8        A     3      1        7
   99       A     4      1        7
  200       A     3      1        7
  200       A     3      1        7
  200       A     3      1        7

当我使用“SELECT * FROM #test”

时，我想得到一些看起来像这样的东西

  batchno | Q | number | DayNo | total
   2        A     1      1        2
   2        A     1      1        2
   8        A     3      1        2
   8        A     3      1        2
   99       A     4      1        null
  200       A     3      1        3
  200       A     3      1        3
  200       A     3      1        3

Answer 1

我想你想要：

UPDATE #test
    set total = (select count(batchno)as total
                 from #test t2
                 where t2.batchno = t.batchno and (number=1 or number=3) and DayNo=1)
    from #test t;

Answer 2

你非常接近，只需使用一个temptable来保存每个BatchNo的计数并使用它。请试试这个：

select BatchNo,count(*) as total 
into #temp
from #test t1 
where (number=1 or number=3) and DayNo=1
Group by BatchNo 

UPDATE #test 
set total= (select total
            from #temp t
            where t.BatchNo = #test.BatchNo)

Answer 3

我认为您可以使用窗口功能：

select t.*, count(*) over(partition by batchno) as total 
from   #test

Answer 4

在子集中，要对集合应用更新，您的条件是将所有值设置为等于该子查询。您可能需要考虑更新的where子句或使用可以与表连接的CTE。

;with cte as (
  select count(batchno)as total --this will be sigma of all batchno, my bad...
  from @test 
  where (number=1 or number=3) and DayNo=1
)
update @test
set total = (select total from cte)
where (number=1 or number=3) and DayNo=1

SQL Update不适用于Group by

4 个答案: