如何在SQL Server中有效地获取上一行和下一行的值

Question

说我有这些行,

InstrumentID

547
698
708

InstrumentID不是自动生成的列.

假如我在程序中传递参数为698,我应该将之前的值设为547,将下一个值设为708.如何在SQL中有效地执行此操作？

我有这个程序,但效率不高(而且不正确).

Alter PROCEDURE GetNextAndPreviousInsturmentID
(
    @InstrumentID   varchar(14),
    @PreviousInstrumentID   varchar(14) OUT,
    @NextInstrumentID   varchar(14) OUT
)
AS
BEGIN
    Declare @RowNum int = 0

    Select @RowNum = ROW_NUMBER() Over (Order by Cast(@InstrumentID as decimal(18))) From Documents Where InstrumentID = @InstrumentID 

    ;With normal As
    (   
        Select ROW_NUMBER() Over (Order by Cast(@InstrumentID as decimal(18))) as RowNum, Cast(InstrumentID as decimal(18)) as InstrumentID
            From Documents 
    )
    Select @PreviousInstrumentID = InstrumentID From normal
        Where RowNum = @RowNum - 1
    Select @NextInstrumentID = InstrumentID From normal
        Where RowNum = @RowNum + 1

END
GO

Answer 1

这是一个更简单的解决方案,但仍然更有效

SELECT P.PreviousID, N.NextID
FROM
(SELECT  MAX(D.InstrumentID) PreviousID
FROM Documents D
WHERE InstrumentID < @InstrumentID) P
CROSS JOIN
(SELECT  MIN(D.InstrumentID) NextID
FROM Documents D
WHERE InstrumentID > @InstrumentID) N

Answer 2

尝试这个：

Alter PROCEDURE GetNextAndPreviousInsturmentID
(
    @InstrumentID   varchar(14),
    @PreviousInstrumentID   varchar(14) OUT,
    @NextInstrumentID   varchar(14) OUT
)
AS
BEGIN

    Declare @Ids TABLE(Id varchar(14))

    ;With normal As
    (   
        --Numerate our rows
        Select ROW_NUMBER() Over (Order by Cast(Documents.InstrumentID as decimal(18)) as RowNumber,
               Documents.InstrumentID
        From Documents 

    )
    --Insert three rows from our table with our id and previos/next id
    INSERT INTO @Ids(Id)
    SELECT TOP(3) normal.InstrumentID
    FROM normal
    WHERE RowNumber >=
        (
            SELECT RowNumber - 1
            FROM normal
            WHERE normal.InstrumentID = @InstrumentID
        )
    ORDER BY normal.RowNumber
    --select next and previos ids

    SELECT @PreviousInstrumentID = Min(CAST(Id as decimal(18))),
           @NextInstrumentID = MAX(CAST(Id as decimal(18)))
    FROM @Ids
END
GO

在 MS SQL 2012 中，我们有新的窗口函数，如 FIRST_VALUE 和 LAST_VALUE，不幸的是在 sql 2008 中这些函数丢失了。