我需要平鋪SQL Server行到列使用樞軸

Question

我一直在嘗試使用SQL Server樞軸一段時間，但我似乎並沒有得到正確的。我讀過一堆的答案，但不明白數據透視是如何工作的。

我在寫存儲過程。我有表1（作爲TVP收到），並且需要使其看起來像表2（see this image for tables）。

重要說明：Table1.valueTypeID中的值不能硬編碼到邏輯中，因爲它們總是可以更改。因此，邏輯必須是超級動態的。

請參閱下面的代碼。數據透視表位於存儲過程的末尾。

  -- Create date: 12/10/2013 
      -- Description: select all the contacts associated with received accountPassport 
      -- ============================================= 
      ALTER PROCEDURE [dbo].[selectContactsPropsByAccountPassport] 
       -- Add the parameters for the stored procedure here 
       @accountPassport int, 
       @valueTypeFiltersTVP valueTypeFiltersTVP READONLY 
      AS 
      BEGIN 
       -- SET NOCOUNT ON added to prevent extra result sets from 
       -- interfering with SELECT statements. 
       SET NOCOUNT ON; 

       -- Insert statements for procedure here 
       DECLARE @accountID int; 
       DECLARE @contactsAppAccountPassport int; 
       DECLARE @searchResults TABLE 
        (
         resultContactID int 
        ); 
       DECLARE @resultContactID int; 

       DECLARE @contactsPropsForReturn TABLE 
        (
         contactID int, 
         valueTypeID int, 
         value varchar(max) 
        ); 

       create table #contactsPropsForReturnFiltered(contactID int,valueTypeID int, value varchar(max)) 

       /* 
       DECLARE #contactsPropsForReturnFiltered TABLE 
        (
         contactID int, 
         valueTypeID int, 
         value varchar(max) 
        ); 
       */ 

      --2. get @contactsAppAccountPassport associated with recieved @accountPassport 
       -- go into dbo.accounts and get the @accountID associated with this @accountPassport 
       SELECT 
        @accountID = ID 
       FROM 
        dbo.accounts 
       WHERE 
        passport = @accountPassport 

       -- go into dbo.accountsProps and get the value (@contactsAppAccountPassport) where valueType=42 and accountID = @accountID 
       SELECT 
        @contactsAppAccountPassport = value 
       FROM 
        dbo.accountsProps 
       WHERE 
        (valueTypeID=42) AND (accountID = @accountID) 

      --3. get all the contact ID's from dbo.contacts associated with @contactsAppAccountPassport 
       INSERT INTO 
        @searchResults 
       SELECT 
        ID 
       FROM 
        dbo.contacts 
       WHERE 
        contactsAppAccountPassport = @contactsAppAccountPassport 

      --4. Get the props of all contact ID's from 3. 

       --start for each loop....our looping object is @resultContactID row. if there are more rows, we keep looping. 
       DECLARE searchCursor CURSOR FOR 
        SELECT 
         resultContactID 
        FROM 
         @searchResults 

        OPEN searchCursor 

         FETCH NEXT FROM searchCursor INTO @resultContactID 

         WHILE (@@FETCH_STATUS=0) 
         BEGIN 
          INSERT INTO 
           @contactsPropsForReturn 
          SELECT 
           contactID, 
           valueTypeID, 
           value 
          FROM 
           dbo.contactsProps 
          WHERE 
           contactID = @resultContactID 
          FETCH NEXT FROM searchCursor INTO @resultContactID 
         END --end of WHILE loop 

        --end of cursor (both CLOSE and DEALLOCATE necessary) 
        CLOSE searchCursor 
        DEALLOCATE searchCursor 

        -- select and return only the props that match with the requested props 
        -- (we don't want to return all the props, only the ones requested) 
        INSERT INTO 
         #contactsPropsForReturnFiltered 
        SELECT 
         p.contactID, 
         p.valueTypeID, 
         p.value 
        FROM 
         @contactsPropsForReturn as p 
        INNER JOIN 
         @valueTypeFiltersTVP as f 
        ON 
         p.valueTypeID = f.valueTypeID 



        DECLARE @cols AS NVARCHAR(MAX), 
        @query AS NVARCHAR(MAX); 

        SET @cols = STUFF((SELECT distinct ',' + QUOTENAME(ValueTypeId) 
         FROM #contactsPropsForReturnFiltered 
         FOR XML PATH(''), TYPE 
         ).value('.', 'NVARCHAR(MAX)') 
        ,1,1,''); 

      set @query = 'SELECT contactid, ' + @cols + ' from 
         (
          select contactid 
           , Value 
           ,ValueTypeId 
          from #contactsPropsForReturnFiltered 
         ) x 
         pivot 
         (
          min(Value) 
          for ValueTypeId in (' + @cols + ') 
         ) p '; 

      execute(@query); 

      END 

Answer 1

您需要在您的情況下使用動態數據透視表。請嘗試以下操作

create table table1 
(
    contactid int, 
    ValueTypeId int, 
    Value varchar(100) 
); 

insert into table1 values (56064, 40, 'Issac'); 
insert into table1 values (56064, 34, '(123)456-7890'); 
insert into table1 values (56065, 40, 'Lola'); 
insert into table1 values (56065, 34, '(123)456-7832'); 
insert into table1 values (56068, 40, 'Mike'); 
insert into table1 values (56068, 41, 'Gonzalez'); 
insert into table1 values (56068, 34, '(123)456-7891'); 


DECLARE @cols AS NVARCHAR(MAX), 
    @query AS NVARCHAR(MAX); 

SET @cols = STUFF((SELECT distinct ',' + QUOTENAME(ValueTypeId) 
      FROM table1 
      FOR XML PATH(''), TYPE 
      ).value('.', 'NVARCHAR(MAX)') 
     ,1,1,''); 

set @query = 'SELECT contactid, ' + @cols + ' from 
      (
       select contactid 
        , Value 
        ,ValueTypeId 
       from table1 
      ) x 
      pivot 
      (
       min(Value) 
       for ValueTypeId in (' + @cols + ') 
      ) p '; 


execute(@query); 

drop table table1 

Answer 2

爲什麼您需要以這種方式顯示數據？

在許多情況下，客戶端比數據庫引擎在旋轉方面更好。例如，SQL Server Reporting Services可以通過矩陣控制輕鬆實現。同樣，如果你正在編寫一個網頁，例如Asp.Net，你可以快速運行記錄集，將你的數據傳遞給一個新的數據表示（同時收集唯一的值），然後通過新的數據對象吐出HTML來呈現結果。

如果可能的話，請讓客戶端代替服務器執行pivoting操作。

UPDATE：

如果你真的想使用動態SQL表變量，你可以在SQL Server 2008和了就好了。這裏有一個腳本示例：

USE tempdb 
GO 
CREATE TYPE IDList AS TABLE (
    ID int 
); 
GO 
DECLARE @SQL nvarchar(max); 
SET @SQL = 'SELECT * FROM @TransactionIDs WHERE ID >= 4;' 
DECLARE @TransactionIDs IDLIst; 
INSERT @TransactionIDs VALUES (1), (2), (4), (8), (16); 
EXEC sp_executesql @SQL, N'@TransactionIDs IDList READONLY', @TransactionIDs; 
GO 
DROP TYPE IDList;