Question

这里已经有一些类似的问题了，但它们似乎对我没用。我需要查询XML文件以从中提取数据，因此我们可以将查询结果用于其他目的。我在网上搜索了一个方法来执行此操作，似乎value（）方法是推荐的方法。我用以下代码尝试了这个：

DECLARE @x XML
SET @x = 
'<?xml version="1.0" encoding="UTF-8"?>
<BlockOrderMessage xmlns="http://www.test.com/production/block"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.test.com/production/block file:/C:/Users/test.xsd"
BlockNumber="BlockNumber1">
<BlockStartTime>01:01:01.001</BlockStartTime>
<ProductionDate>2006-05-04</ProductionDate>
<BlockType>Bloc</BlockType>
<FlightOrders>
    <FlightOrder>
        <Flight>
            <FlightNr>FlightNr0</FlightNr>
            <DepartureDate>2006-05-04</DepartureDate>
            <DepartureTime>01:01:01.001</DepartureTime>
            <AircraftType>AircraftType0</AircraftType>
            <AircraftSeatConfiguration>AircraftSeatConfiguration0</AircraftSeatConfiguration>
        </Flight>
        <CATC>CATC0</CATC>
    </FlightOrder>
    <FlightOrder>
        <Flight>
            <FlightNr>FlightNr1</FlightNr>
            <DepartureDate>2006-05-04</DepartureDate>
            <DepartureTime>01:01:01.001</DepartureTime>
            <AircraftType>AircraftType1</AircraftType>
            <AircraftSeatConfiguration>AircraftSeatConfiguration1</AircraftSeatConfiguration>
        </Flight>
   </FlightOrder>
</FlightOrders>

SELECT @x.value('(/BlockOrderMessage/Blocktype)[1]','int') AS 'BlockType',
   @x.value('(/BlockOrderMessage/FlightOrders/FlightOrder/Flight/FlightNr)[1]','VARCHAR (20)') AS 'FlightNr',
   @x.value('(/BlockOrderMessage/FlightOrders/FlightOrder/Flight/AircraftType)[1]','VARCHAR (20)') AS 'AircraftType'

然后我收到三列的查询结果（到目前为止一直很好），但所有三列的记录都是NULL。当我删除BlockOrderMessage中的名称空间声明时，它确实有效，所以我假设我需要在查询中的某处声明这些名称空间，但我找不到如何。有人怎么做这个？

提前致谢！

Answer 1

HY，首先，我认为它区分大小写，因此将Blocktype更正为BlockType。不要将BlockType转换为int，因为它是string所以请使用nvarchar(max)。在查询中使用xml命名空间，如下所示 ; WITH XMLNAMESPACES (default 'http://www.test.com/production/block')

SELECT @ x.value（'（/ BlockOrderMessage / BlockType）[1]'，'varchar(max)'）AS'BlockType'， @ x.value（'（/ BlockOrderMessage / FlightOrders / FlightOrder / Flight / FlightNr）[1]'，'VARCHAR（20）'）AS'FlightNr'， @ x.value（'（/ BlockOrderMessage / FlightOrders / FlightOrder / Flight / AircraftType）[1]'，'VARCHAR（20）'）AS'AircraftType'`

以下是完整查询

DECLARE @x XML
SET @x = 
'<?xml version="1.0" encoding="UTF-8"?>
<BlockOrderMessage xmlns="http://www.test.com/production/block"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.test.com/production/block file:/C:/Users/test.xsd"
BlockNumber="BlockNumber1">
<BlockStartTime>01:01:01.001</BlockStartTime>
<ProductionDate>2006-05-04</ProductionDate>
<BlockType>Bloc</BlockType>
<FlightOrders>
    <FlightOrder>
        <Flight>
            <FlightNr>FlightNr0</FlightNr>
            <DepartureDate>2006-05-04</DepartureDate>
            <DepartureTime>01:01:01.001</DepartureTime>
            <AircraftType>AircraftType0</AircraftType>
            <AircraftSeatConfiguration>AircraftSeatConfiguration0</AircraftSeatConfiguration>
        </Flight>
        <CATC>CATC0</CATC>
    </FlightOrder>
    <FlightOrder>
        <Flight>
            <FlightNr>FlightNr1</FlightNr>
            <DepartureDate>2006-05-04</DepartureDate>
            <DepartureTime>01:01:01.001</DepartureTime>
            <AircraftType>AircraftType1</AircraftType>
            <AircraftSeatConfiguration>AircraftSeatConfiguration1</AircraftSeatConfiguration>
        </Flight>
   </FlightOrder>
</FlightOrders>
</BlockOrderMessage>'
; WITH XMLNAMESPACES (default 'http://www.test.com/production/block')

SELECT @x.value('(/BlockOrderMessage/BlockType)[1]','varchar(50)') AS 'BlockType',
   @x.value('(/BlockOrderMessage/FlightOrders/FlightOrder/Flight/FlightNr)[1]','VARCHAR (20)') AS 'FlightNr',
   @x.value('(/BlockOrderMessage/FlightOrders/FlightOrder/Flight/AircraftType)[1]','VARCHAR (20)') AS 'AircraftType'

查询从XML读取数据

1 个答案: