Question

我希望使用像此Data

这样的东西合并DataTable行

A Ar 1 3 A Ab 3 4 B Bl 3 5 B Bk 5 2 M Mj 4 5

到像这样的DataTable

A Ar 1 3 Ab 3 4
B Bl 3 5 Bk 5 2
M Mj 4 5 Null Null Null

是否有任何TSQL语句可以执行此操作？

Answer 1

这很简单，因为它的变量数量有限。第一部分是设置临时表，因为我不知道你的列名或任何东西。

fields
 => {"0"=>{"field"=>"something", "field_type"=>"something type", "validation"=>{"enabled"=>"true", "persisted"=>"false", "another thing"=>"false"}}, "1"=>{"field"=>"something else", "field_type"=>"something else type", "validation"=>{"enabled"=>"true", "persisted"=>"false"}}} 
 copy = fields.reduce({}) do |acc,(k,v)|
   acc[k] = {
     'fields' => v['field'],
     'field_type' => v['field_type'],
     'validation' => v['validation'].reduce({}) {|acc,(k,v)| acc[k] = (v == "true" ) ? true : false; acc; }
   }
   acc
 end
  => {"0"=>{"fields"=>"something", "field_type"=>"something type", "validation"=>{"enabled"=>true, "persisted"=>false, "another thing"=>false}}, "1"=>{"fields"=>"something else", "field_type"=>"something else type", "validation"=>{"enabled"=>true, "persisted"=>false}}}

Answer 2

试试这个：

--create temp table for OP data sample 
DECLARE @YourData AS TABLE
    (
      C1 VARCHAR(1) ,
      C2 VARCHAR(2) ,
      C3 INT ,
      C4 INT
    )
INSERT  @YourData
        ( C1, C2, C3, C4 )
VALUES  ( 'A', 'Ar', 1, 3 ),
        ( 'A', 'Ab', 3, 4 ),
        ( 'B', 'Bl', 3, 5 ),
        ( 'B', 'Bk', 5, 2 ),
        ( 'M', 'Mj', 4, 5 ) 
--final query
;WITH    cte
          AS ( SELECT   C1 ,
                        C2 ,
                        C3 ,
                        C4 ,
                        ROW_NUMBER() OVER ( PARTITION BY C1 ORDER BY C2 ) AS RN
               FROM     @YourData
             )
    SELECT  c1.C1 ,
            c1.C2 ,
            c1.C3 ,
            c1.C4 ,
            c2.C1 ,
            c2.C2 ,
            c2.C3 ,
            c2.C4 
    FROM    cte AS c1 LEFT JOIN cte AS c2 ON c1.C1 = c2.C1 AND c2.RN > 1
    WHERE c1.rn = 1

在Sql中合并Datarow

2 个答案: