1

我有两个 sql 表，并正在寻找一个 sql 查询以从 Table2.ValueDescription 列中针对 Table1.ValueID 列中的每个数值选择数据并将结果保存在 Table3

表格1：

ID  ValueID
1   1,12,14
2   3,5,15
3   2,6,13,16

表2：

ValueID   ValueDescription
1         Motor
2         Low
3         Failed
4         New Install
5         New Item
6         Max Value
7         AC Current
8         DC Current
9         Not Reached
10        NA
11        Cutoff
12        Manual
13        Automatic
14        Device Not Found
15        Halt
16        Renew

预期结果：

表3：

ID  ValueID       Result
1   1,12,14       Motor,Manual,Device Not Found
2   3,5,15        Failed,New Item,Halt
3   2,6,13,16     Low,Max Value,Automatic,Renew

使用 SQL Server Management Studio

这是我尝试过的查询

 SELECT Table1.ValueID,
   Stuff((SELECT ',' + CAST(Table2.Description AS VARCHAR(100))
           FROM Table2
          WHERE Table1.ValueID LIKE Table2.ValueID
            FOR Xml Path('')),1,1,'')
FROM Table1

我在这里想念什么？

4

4 回答 4

2

如果您确实使用 SQL Server 2017，则可以同时使用 STRING_SPLIT 和 STRING_AGG 函数。它们使语法非常简单。

IF OBJECT_ID('tempdb..#Table1', 'U') IS NOT NULL 
DROP TABLE #Table1;

CREATE TABLE #Table1 (
    ID INT NOT NULL PRIMARY KEY,
    ValueID VARCHAR(50) NOT NULL 
    );
INSERT #Table1 (ID, ValueID) VALUES
    (1, '1,12,14'),
    (2, '3,5,15'),
    (3, '2,6,13,16');

IF OBJECT_ID('tempdb..#Table2', 'U') IS NOT NULL 
DROP TABLE #Table2;

CREATE TABLE #Table2 (
    ValueID INT NOT NULL PRIMARY KEY,
    ValueDescription VARCHAR(50) NOT NULL 
    );
INSERT #Table2(ValueID, ValueDescription) VALUES
    (1, 'Motor'),
    (2, 'Low'),
    (3, 'Failed'),
    (4, 'New Install'),
    (5, 'New Item'),
    (6, 'Max Value'),
    (7, 'AC Current'),
    (8, 'DC Current'),
    (9, 'Not Reached'),
    (10, 'NA'),
    (11, 'Cutoff'),
    (12, 'Manual'),
    (13, 'Automatic'),
    (14, 'Device Not Found'),
    (15, 'Halt'),
    (16, 'Renew');

--SELECT * FROM #Table1 t1;
--SELECT * FROM #Table2 t2;

--========================================================

SELECT 
    t1.ID,
    t1.ValueID,
    csv.Result
FROM
    #Table1 t1
    CROSS APPLY (
            SELECT 
                Result = STRING_AGG(t2.ValueDescription, ',')
            FROM
                STRING_SPLIT(t1.ValueID, ',') ss
                JOIN #Table2 t2
                    ON CONVERT(INT, ss.value) = t2.ValueID
            ) csv;

结果...

ID          ValueID        Result
----------- -------------- -----------------------------------
1           1,12,14        Motor,Manual,Device Not Found
2           3,5,15         Failed,New Item,Halt
3           2,6,13,16      Low,Max Value,Automatic,Renew

编辑：

-

-============================================================================
-- This is an idea that I've been kicking around for a little while now. 
-- It's based on the SUSPICION that, when left to it's own devices. STRING_SPLIT
-- will always retun rows in the original order and attaching a row_number() 
-- to the output, right out of the gate, will effectively serve as an "ItemNumber.
--============================================================================

SELECT 
    t1.ID,
    t1.ValueID,
    csv.Result
FROM
    #Table1 t1
    CROSS APPLY (
            SELECT 
                Result = STRING_AGG(t2.ValueDescription, ',') WITHIN GROUP (ORDER BY rs.rn DESC) -- sort in the descending order for no real eason...
            FROM (
                    SELECT 
                        rn = ROW_NUMBER() OVER (ORDER BY (SELECT NULL)),
                        ValueID = CONVERT(INT, ss.value)
                    FROM 
                        STRING_SPLIT(t1.ValueID, ',') ss
                    ) rs
                JOIN #Table2 t2
                    ON rs.ValueID = t2.ValueID
            ) csv;

ID          ValueID       Result
----------- ------------- --------------------------------
1           1,12,14       Device Not Found,Manual,Motor
2           3,5,15        Halt,New Item,Failed
3           2,6,13,16     Renew,Automatic,Max Value,Low
于 2018-11-30T18:37:39.963 回答
1

这将保持正确的顺序

例子

Select A.* 
      ,B.*
 From  Table1 A
 Cross Apply (
                Select Result = Stuff((Select ',' +B2.ValueDescription 
                  From (
                        Select RetSeq = Row_Number() over (Order By (Select null))
                              ,RetVal = LTrim(RTrim(B.i.value('(./text())[1]', 'varchar(max)')))
                        From  (Select x = Cast('<x>' + replace(A.ValueID,',','</x><x>')+'</x>' as xml).query('.')) as A 
                        Cross Apply x.nodes('x') AS B(i)
                       ) B1
                  Join  Table2 B2 on B1.RetVal=B2.ValueID
                  Order by RetSeq
                  For XML Path ('')),1,1,'') 
             ) B

退货

ID  ValueID     Result
1   1,12,14     Motor,Manual,Device Not Found
2   3,5,15      Failed,New Item,Halt
3   2,6,13,16   Low,Max Value,Automatic,Renew

糟糕——刚刚看到你是 2017 年

于 2018-11-30T18:15:36.847 回答
1

它并没有那么漂亮，但 SQL Server 2017 中的新内置函数确实让这更容易理解，并且仍然可以尊重原始列表的顺序（好吧，我什至无法判断你是否打算按列表中的位置或按数字顺序排序，因为它们是相同的），那么只要它都是整数并且没有重复项：

;WITH explode(ID, ValueID, value, i) AS
(
  SELECT t1.ID,  
    t1.ValueID,
    TRY_CONVERT(int,f.value), 
    CHARINDEX(',' + f.value + ',', ',' + t1.ValueID + ',')
  FROM dbo.Table1 t1
  CROSS APPLY STRING_SPLIT(t1.ValueID, ',') AS f
)
SELECT x.ID, x.ValueID, 
  -- guarantee respect original order:
  Result = STRING_AGG(t2.ValueDescription,',') WITHIN GROUP (ORDER BY x.i)
FROM explode AS x
INNER JOIN dbo.Table2 AS t2
ON x.value = t2.ValueID
GROUP BY x.ID, x.ValueID
ORDER BY x.ID;

如果顺序无关紧要，并且您确定 in 的ValueID列表中不能有重复项或非整数Table1，则要简单得多：

;WITH explode(ID, ValueID, value) AS
(
  SELECT t1.ID, t1.ValueID, f.value
  FROM dbo.Table1 t1
  CROSS APPLY STRING_SPLIT(t1.ValueID, ',') AS f
)
SELECT x.ID, x.ValueID, STRING_AGG(t2.ValueDescription,',')
FROM explode AS x
INNER JOIN dbo.Table2 AS t2
ON x.value = t2.ValueID
GROUP BY x.ID, x.ValueID
ORDER BY x.ID;
于 2018-11-30T18:59:39.177 回答
0

你可以这样做

SELECT *,
       STUFF(
         (
           SELECT ',' + ValueDescription
           FROM T2
           WHERE ',' + T1.ValueID + ',' LIKE '%,' + CAST(T2.ValueID AS VARCHAR) + ',%'
           FOR XML PATH('')
         ),
         1, 1, ''
       ) ValueDescription
FROM T1;

回报：

+----+-----------+-------------------------------+
| ID |  ValueID  |       ValueDescription        |
+----+-----------+-------------------------------+
|  1 |   1,12,14 | Motor,Manual,Device Not Found |
|  2 |    3,5,15 | Failed,New Item,Halt          |
|  3 | 2,6,13,16 | Low,Max Value,Automatic,Renew |
+----+-----------+-------------------------------+

演示

于 2018-11-30T18:39:57.780 回答