从 SQL 表生成 XML 路径格式

Question

我试图从 SQL 表中获取 XML：

我的桌子

------------
-- Table1 --
------------

ID    Flight1    Flight2
--------------------------
1     F0123      F0789
2     F0345      F0678

Query:

Select
    A.[ID],
    A.[Flight1] as "FlightDescription/Number",
    A.[Flight2] as "FlightDescription/Number"
from
    [Table1] A
for xml path('Flight'), root('Flights')

我的预期结果是：

 <Flights>
  <Flight>
    <ID>1</ID>
    <FlightDescription>
        <Number>F0123</Number>
    </FlightDescription>
    <FlightDescription>
        <Number>F0789</Number>
    </FlightDescription>
  </Flight>
  <Flight>
    <ID>2</ID>
    <FlightDescription>
        <Number>F0345</Number>
    </FlightDescription>
    <FlightDescription>
        <Number>F0678</Number>
    </FlightDescription>
  </Flight>
</Flights>

但我得到的是这个：

<Flights>
  <Flight>
    <ID>1</ID>
    <FlightDescription>
        <Number>F0123F0789</Number>
    </FlightDescription>
  </Flight>
  <Flight>
    <ID>2</ID>
    <FlightDescription>
        <Number>F0345F0678</Number>
    </FlightDescription>
  </Flight>
</Flights>

我可以弄清楚...在我的表格中，每个 ID 都有超过 4 个航班号，所以我想知道是否有办法让所有这些都以我需要的方式。

提前致谢！

Answer 1

在两个 FlightDescription/Number 元素/节点之间创建一个空节点。

declare @f table
(
Id int,
Flight1 varchar(20),
Flight2 varchar(20)
);

insert into @f(Id, Flight1, Flight2)
values
(1, 'F0123', 'F0789'),
(2, 'F0345', 'F0678');

Select
    A.[ID],
    A.[Flight1] as 'FlightDescription/Number',
    '',
    A.[Flight2] as 'FlightDescription/Number'
from
    @f A
for xml path('Flight'), root('Flights');

Answer 2

这是另一种稍微复杂的方法。 XQuery 及其 FLWOR 表达式。通过这种方式，您可以显式地塑造您的 XML。它很容易创建、理解、进行任何修改并在以后进行维护。

SQL

-- DDL and sample data population, start
DECLARE @tbl TABLE (ID INT PRIMARY KEY, Flight1 VARCHAR(20), Flight2 VARCHAR(20));

INSERT INTO @tbl (ID, Flight1, Flight2) VALUES
(1, 'F0123', 'F0789'),
(2, 'F0345', 'F0678');
-- DDL and sample data population, end

SELECT (
SELECT * 
FROM @tbl
FOR XML PATH('r'), TYPE, ROOT('root')).query('<Flights>
{
    for $x in /root/r
    return <Flight>
        {$x/ID}
        <FlightDescription>
            <number>{data($x/Flight1)}</number>
            <number>{data($x/Flight2)}</number>
        </FlightDescription>
    </Flight>
}
</Flights>'
);

输出

<Flights>
  <Flight>
    <ID>1</ID>
    <FlightDescription>
      <number>F0123</number>
      <number>F0789</number>
    </FlightDescription>
  </Flight>
  <Flight>
    <ID>2</ID>
    <FlightDescription>
      <number>F0345</number>
      <number>F0678</number>
    </FlightDescription>
  </Flight>
</Flights>