我在使用旨在将结果数据返回为 XML 的 SQL 查询时遇到问题。下面是一个代码转储,向您展示所有发生的事情:
SQL 查询(注意:表名和列名已编辑(
with resultdata as
(
SELECT
(
select * from Table1 (nolock)
where column1 = 99999 and column2 = -1 for xml auto, type
) as tabledata
UNION ALL
SELECT
(
select * from Table2 (nolock)
where column1 = 99999 and column2 = -1 for xml auto, type
)
UNION ALL
SELECT
(
select * from Table3 (nolock)
where column1 = 99999 and column2 = -1 for xml auto, type
)
UNION ALL
SELECT
(
select * from Table4 (nolock)
where column1 = 99999 and column2 = -1 for xml auto, type
)
UNION ALL
SELECT
(
select * from Table5 (nolock)
where column1 = 99999 and column2 = -1 for xml auto, type
)
UNION ALL
SELECT
(
select * from Table6 (nolock)
where column1 = 99999 and column2 = -1 for xml auto, type
)
UNION ALL
SELECT
(
select * from Table7 (nolock)
where column1 = 99999 and column2 = -1 for xml auto, type
)
UNION ALL
SELECT
(
select * from Table8 (nolock)
where column1 = 99999 and column2 = -1 for xml auto, type
)
)
select * from resultdata result for xml auto, elements
这将返回如下所示的 XML 结果(大多数 XML 已编辑,注释是实际数据所在的位置(:
<result>
<tabledata>
<!--Table1 results-->
</tabledata>
</result>
<result>
<tabledata>
<!--Table2 results-->
</tabledata>
</result>
<result>
<tabledata>
<!--Table3 results-->
</tabledata>
</result>
<result>
<tabledata>
<!--Table4 results-->
</tabledata>
</result>
<result>
<tabledata>
<!--Table5 results-->
</tabledata>
</result>
<result>
<tabledata>
<!--Table6 results-->
</tabledata>
</result>
<result>
<tabledata>
<!--Table7 results-->
</tabledata>
</result>
<result>
<tabledata>
<!--Table8 results-->
</tabledata>
</result>
显然这是格式错误的XML,但我似乎无法对其进行返工,以便它以正确的格式为我提供结果,如下所示:
<result>
<tabledata>
<!--Table1 results-->
</tabledata>
<tabledata>
<!--Table2 results-->
</tabledata>
<tabledata>
<!--Table3 results-->
</tabledata>
<tabledata>
<!--Table4 results-->
</tabledata>
<tabledata>
<!--Table5 results-->
</tabledata>
<tabledata>
<!--Table6 results-->
</tabledata>
<tabledata>
<!--Table7 results-->
</tabledata>
<tabledata>
<!--Table8 results-->
</tabledata>
</result>
作为旁注,这是对我们现有查询的重写,这就是为什么语法大多是这样。我的一位同事开始重新设计它,基本上给了我我在这里发布的内容,但是我一直在努力尝试使用他的更改来使其工作。如果我需要报废它并从头开始,我这样做没有问题。
另外,作为另一个说明,我希望它看起来像的 XML 必须是这样的,因为它最终由我无法控制的 XSLT 使用。此查询的旧版本将每个 tabledata 元素作为不同的列名返回,然后在调用它的 C# 代码中替换了一个字符串。在此 XML(可以是 100k+ 行(上进行多个字符串替换存在性能问题,因此答案是更改查询以按我们需要的方式返回数据。
只是另一种选择。 这将返回您想要的结果。
Select (select * from Table1 (nolock) where column1 = 99999 and column2 = -1 for XML auto, type, root('tabledata') )
,(Select * from Table2 (nolock) where column1 = 99999 and column2 = -1 for XML auto, type, root('tabledata') )
,(Select * from Table3 (nolock) where column1 = 99999 and column2 = -1 for XML auto, type, root('tabledata') )
For XML Path(''),Root('results')
在 SQL Server 中,XML 变量、列或 FOR XML 查询结果表示一个"XML 片段",没有单个顶级元素。
对于 XML 查询 如果需要 XML 文档(具有顶级根元素(,请为 FOR XML 添加 ROOT 参数。
如果我正确理解了您的问题,您应该将每个表的查询合并在一起,然后应用 XML 格式。喜欢这个。。。
WITH resultdata AS
(
SELECT (
SELECT *
FROM (
SELECT *
FROM Table1 (NOLOCK)
WHERE column1 = 99999
AND column2 = -1
UNION ALL
SELECT *
FROM Table2 (NOLOCK)
WHERE column1 = 99999
AND column2 = -1
UNION ALL
SELECT *
FROM Table3 (NOLOCK)
WHERE column1 = 99999
AND column2 = -1
UNION ALL
SELECT *
FROM Table4 (NOLOCK)
WHERE column1 = 99999
AND column2 = -1
UNION ALL
SELECT *
FROM Table5 (NOLOCK)
WHERE column1 = 99999
AND column2 = -1
UNION ALL
SELECT *
FROM Table6 (NOLOCK)
WHERE column1 = 99999
AND column2 = -1
UNION ALL
SELECT *
FROM Table7 (NOLOCK)
WHERE column1 = 99999
AND column2 = -1
UNION ALL
SELECT *
FROM Table8 (NOLOCK)
WHERE column1 = 99999
AND column2 = -1
) AS x
FOR XML AUTO, TYPE
) AS tabledata
)
SELECT * FROM resultdata AS result FOR XML AUTO, ELEMENTS;
以下解决方案怎么样,它允许从具有不同结构的数据库表中构造最终的XML。
.SQL
-- DDL and sample data population, start
DECLARE @tbl1 TABLE (ID INT IDENTITY(1,1) PRIMARY KEY, city VARCHAR(30));
INSERT INTO @tbl1
VALUES
('Miami')
, ('Orlando');
DECLARE @tbl2 TABLE (ID INT IDENTITY(1,1) PRIMARY KEY, [state] VARCHAR(30));
INSERT INTO @tbl2
VALUES
('Florida')
, ('Texas');
-- DDL and sample data population, end
WITH resultdata (tabledata) AS
(
SELECT
(
SELECT * FROM @tbl1
FOR XML PATH('row'), TYPE, ROOT('tbl1')
) AS [tbl1]
UNION ALL
SELECT
(
SELECT * FROM @tbl2
FOR XML PATH('row'), TYPE, ROOT('tbl2')
)
)
SELECT *
FROM resultdata
FOR XML PATH(''), TYPE, ROOT('result');
输出 XML
<result>
<tabledata>
<tbl1>
<row>
<ID>1</ID>
<city>Miami</city>
</row>
<row>
<ID>2</ID>
<city>Orlando</city>
</row>
</tbl1>
</tabledata>
<tabledata>
<tbl2>
<row>
<ID>1</ID>
<state>Florida</state>
</row>
<row>
<ID>2</ID>
<state>Texas</state>
</row>
</tbl2>
</tabledata>
</result>