Question

我在SQL Server中编写一个简单的查询：

Select 
    EmpId, EmpName, Sal 
from 
    Emp 
where  
    EmpId in (10,9,5,7,3,8);

我希望得到的输出顺序是相同的，即; 10,9,5,7,3,8

实际上，无论我给出什么结果，都会以给定的顺序显示按升序或降序排列。

我该怎么做？请帮忙。

Answer 1

无法原生地执行此操作。尝试：

SELECT EmpId,EmpName,Sal
FROM Emp
WHERE EmpId IN (10,9,5,7,3,8)
ORDER BY CASE EmpId
    WHEN 10 THEN 1
    WHEN 9 THEN 2
    WHEN 5 THEN 3
    WHEN 7 THEN 4
    WHEN 3 THEN 5
    WHEN 8 THEN 6
    ELSE 7
END;

Answer 2

您可以使用表变量来传递输入。您必须按所需顺序将记录插入此表变量。

Declare @empids table(id int identity(1,1),empid int)
insert into @empids values(10),(9),(5),(7),(3),(8)

Select e.EmpId,e.empname,e.sal from Emp e
join @empids t on  e.EmpId = t.empid 
order by t.id

试试这个。

Answer 3

您可以奇怪的方式使用CHARINDEX函数：在逗号分隔列表中搜索id并按位置排序结果。

考虑此列表例如10,9,5,7,3,8 ...子串10出现在1 ^st位置，而9出现在4 ^th。只需按子串位置排序。

CREATE TABLE Emp
    (EmpId int, EmpName varchar(100), Sal int)
;

INSERT INTO Emp
    (EmpId, EmpName, Sal)
VALUES
    (1, 'John', NULL),
    (2, 'Jane', NULL),
    (3, 'Smith', NULL),
    (4, 'Doe', NULL),
    (5, 'Ben', NULL),
    (6, 'Steve', NULL),
    (7, 'Andrew', NULL),
    (8, 'Simon', NULL),
    (9, 'Jack', NULL),
    (10, 'Allen', NULL)
;

SELECT
    EmpId, EmpName, Sal
FROM
    Emp
WHERE
    EmpId in (10,9,5,7,3,8)
ORDER BY
    CHARINDEX(CONCAT(',', EmpId, ','), CONCAT(',', '10,9,5,7,3,8', ','))
;

结果：

EmpId | EmpName | Sal
------+---------+-----
10    | Allen   | NULL
9     | Jack    | NULL
5     | Ben     | NULL
7     | Andrew  | NULL
3     | Smith   | NULL
8     | Simon   | NULL

Answer 4

如果列表是逗号分隔的字符串，则可以动态执行此操作。首先，您必须具有分离器功能。以下是Jeff Moden撰写的DelimitedSplit8k：

CREATE FUNCTION [dbo].[DelimitedSplit8K](
    @pString VARCHAR(8000), @pDelimiter CHAR(1)
)
RETURNS TABLE WITH SCHEMABINDING AS
RETURN
WITH E1(N) AS (
    SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL 
    SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1
)
,E2(N) AS (SELECT 1 FROM E1 a, E1 b)
,E4(N) AS (SELECT 1 FROM E2 a, E2 b)
,cteTally(N) AS(
    SELECT TOP (ISNULL(DATALENGTH(@pString), 0)) ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) FROM E4
)
,cteStart(N1) AS(
    SELECT 1 UNION ALL 
    SELECT t.N+1 FROM cteTally t WHERE SUBSTRING(@pString, t.N, 1) = @pDelimiter
),
cteLen(N1, L1) AS(
SELECT 
    s.N1,
    ISNULL(NULLIF(CHARINDEX(@pDelimiter, @pString, s.N1),0) - s.N1, 8000)
FROM cteStart s
)
SELECT 
    ItemNumber = ROW_NUMBER() OVER(ORDER BY l.N1),
    Item       = SUBSTRING(@pString, l.N1, l.L1)
FROM cteLen l

然后，您将empId的列表声明为csv字符串并使用拆分器：

DECLARE @empIds VARCHAR(MAX) = '10,9,5,7,3,8';

SELECT e.EmpId, e.EmpName, e.Sal 
FROM Emp e
INNER JOIN dbo.DelimitedSplit8K(@empIds, ',') s
    ON s.Item = l.EmpId
ORDER BY s.ItemNumber

Answer 5

以下查询将为您提供确切的结果（没有订购）：

SELECT EmpId,EmpName,Sal
FROM Emp
WHERE EmpId IN (10)
union all
SELECT EmpId,EmpName,Sal
FROM Emp
WHERE EmpId IN (9)
union all
SELECT EmpId,EmpName,Sal
FROM Emp
WHERE EmpId IN (5)
union all
SELECT EmpId,EmpName,Sal
FROM Emp
WHERE EmpId IN (7)
union all
SELECT EmpId,EmpName,Sal
FROM Emp
WHERE EmpId IN (3)
union all
SELECT EmpId,EmpName,Sal
FROM Emp
WHERE EmpId IN (8)

Answer 6

如果Ids是作为输入参数传递给存储过程的变量，则可以使用CTE将其拆分。

--@inputIDs VARCHAR(300) => '10,9,5,7,3,8'

;WITH MyIds AS
(
    SELECT 1 AS Position, CONVERT(INT, LEFT(@inputIds, CHARINDEX(',', @inputIDs)-1)) AS MyId, 
        RIGHT(@inputIds, LEN(@inputIds) - CHARINDEX(',', @inputIDs)) AS Remainder
    WHERE CHARINDEX(',', @inputIDs)>0
    UNION ALL
    SELECT Position +1  AS Position, CONVERT(INT, LEFT(Remainder, CHARINDEX(',', Remainder)-1)) AS MyId, 
        RIGHT(Remainder, LEN(Remainder) - CHARINDEX(',', Remainder)) AS Remainder
    FROM MyIds 
    WHERE CHARINDEX(',', Remainder)>0
    UNION ALL
    SELECT Position +1 AS Position, CONVERT(INT, Remainder) AS MyId, 
        NULL AS Remainder
    FROM MyIds 
    WHERE CHARINDEX(',', Remainder)=0
)
SELECT e.EmpId, e.EmpName, e.Sal
FROM Emp AS e INNER JOIN MyIds AS a ON e.EmpId = a.MyId
ORDER BY a.Position

Answer 7

实现这一目标的最简单方法可能是使用表值构造函数作为包含具有排序值的ID的表表达式，然后对此值进行排序：

Select 
    Emp.EmpId, Emp.EmpName, Emp.Sal 
from 
        Emp
    Inner Join
        (
            Values
                (10, 1),
                (9, 2),
                (5, 3),
                (7, 4),
                (3, 5),
                (8, 6)
        )
        EmpIds (EmpId, Sort)
            On
                Emp.EmpId = EmpIds.EmpId
Order By
    EmpIds.Sort Asc

显示没有order by子句的SQL查询的顺序

7 个答案: