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动态SQL查询(变量项和每列的变量项)

stored-procedures sql-server-2008 sql-server sql

0

Brett · 技术社区 · 15 年前

抱歉,这篇文章太长了,但大部分都是我的剧本:

如果我有一张桌子:

(dbo).(People)
ID   Name   Age
1    Joe    28
2    Bob    32
3    Alan   26
4    Joe    27

DECLARE @ID int, @Name nvarchar(25), @Age int
SET @ID = 1
SET @Name = 'Joe'
SET @Age = null

SELECT *
FROM dbo.People
WHERE
(ID = @ID or @ID is null) AND
(Name like @Name or @Name is null) AND
(Age = @Age or @Age is null)

DECLARE @text nvarchar(100)
SET @text = '1, 3'

DECLARE @ids AS TABLE (n int NOT NULL PRIMARY KEY)

--//parse the string into a table
DECLARE @TempString nvarchar(300), @Pos int
SET @text = LTRIM(RTRIM(@text))+ ','
SET @Pos = CHARINDEX(',', @text, 1)
IF REPLACE(@text, ',', '') <> ''
BEGIN
    WHILE @Pos > 0
    BEGIN
        SET @TempString = LTRIM(RTRIM(LEFT(@text, @Pos - 1)))
        IF @TempString <> '' --just: IF @TempString != ''
        BEGIN
            INSERT INTO @ids VALUES (@TempString)
        END
        SET @text = RIGHT(@text, LEN(@text) - @Pos)
        SET @Pos = CHARINDEX(',', @text, 1)
    END
END


SELECT *
FROM   dbo.People
WHERE  
ID IN (SELECT n FROM @ids)

现在,我的问题是我似乎不知道如何将两者结合起来,因为我不能把:

WHERE
(Name like @Name or @Name is null) AND
(Id IN (SELECT n FROM @ids) or @ids is null)

因为@ids永远不会为null(因为它是一个表)

4 回复 | 直到 15 年前

1

0

Cade Roux 15 年前

尝试:

(Id IN (SELECT n FROM @ids) OR NOT EXISTS (SELECT * FROM @ids))

2

1

OMG Ponies 15 年前

可以使用IF语句:

IF LEN(@ids) > 0
BEGIN

  SELECT *
    FROM dbo.People
   WHERE ID IN (SELECT n FROM @ids)

END
ELSE
BEGIN

  SELECT *
    FROM dbo.People

END

否则, consider making the query real dynamic SQL (minding pitfalls of course) .

3

0

Steve Broberg 15 年前

您可以尝试:

NOT EXISTS (SELECT 1 FROM @ids)
OR EXISTS (SELECT 1 FROM @ids where n = Id)

但是这些表最好是小的—这个查询可能无法很好地处理表上的任何索引。

4

0

Andomar 15 年前

快速解决方案:

(`%,' + Id + ',%' like ',' + @ids + ',' or @ids is null)
and (`%,' + Name + ',%' like ',' + @names + ',' or @names is null)

@ids = 1,2 ,第一行给出:

`%,1,%' like ',1,2,'

把逗号前后的空格过滤掉是个好主意