Question

我正在使用sql server，在我的表格中，我有一个＆＃34; ntext＆＃34; column.ntext列中的数据如下

"<?xml version="1.0" encoding="UTF-8"?>
<processEngine id="5000001" instanceName="bg-claritysql.excers">
   <controller heartBeat="2014-11-14T19:35:57"/>
   <loader heartBeat="2014-11-14T19:35:57" queueLength="1"/>
   <conditionWaitList queueLength="1"/>
   <retryWaitList queueLength="0"/>
   <actionWaitList queueLength="0"/>
   <PreConditionPipelineManager load="3.451246679588729E-7" noOfPipelines="2" queueLength="0"
                                recentLoad="8.510423949066926E-6">
           <pipeline heartBeat="2014-10-11T04:14:17" index="1" load="1.0022981644497761E-9"
                name="Pre Condition Pipeline 1"
                recentLoad="1.0022981684681825E-9"
                runTime="3"
                running="false"
                startTime="2014-10-11T04:14:17"/>
   </PreConditionPipelineManager>
   <PostConditionTransitionPipelineManager load="8.273414600907745E-7" noOfPipelines="3" queueLength="0"
  </processEngine>"

我想获取heartBeat，name，recentLoad，runTime，running，startTime值。可以任何人帮助我如何使用SQL查询来做到这一点.. 提前谢谢......

Answer 1

见下文：

declare @str nvarchar(max) = '<processEngine id="5000001" instanceName="bg-claritysql.excers">
   <controller heartBeat="2014-11-14T19:35:57"/>
   <loader heartBeat="2014-11-14T19:35:57" queueLength="1"/>
   <conditionWaitList queueLength="1"/>
   <retryWaitList queueLength="0"/>
   <actionWaitList queueLength="0"/>
   <PreConditionPipelineManager load="3.451246679588729E-7" noOfPipelines="2" queueLength="0" recentLoad="8.510423949066926E-6">
           <pipeline heartBeat="2014-10-11T04:14:17" index="1" load="1.0022981644497761E-9"
                name="Pre Condition Pipeline 1"
                recentLoad="1.0022981684681825E-9"
                runTime="3"
                running="false"
                startTime="2014-10-11T04:14:17"/>
            <pipeline heartBeat="2014-10-11T04:14:17" index="1" load="1.0022981644497761E-9"
                name="Pre Condition Pipeline 1"
                recentLoad="1.0022981684681825E-9"
                runTime="3"
                running="false"
                startTime="2014-10-11T04:14:17"/>
   </PreConditionPipelineManager>
   <PostConditionTransitionPipelineManager load="8.273414600907745E-7" noOfPipelines="3" queueLength="0" />
  </processEngine>'

declare @xml xml = @str

select 
    t.value('(./controller/@heartBeat)[1]', 'datetime') as HeartBeat,
    t.value('(./PreConditionPipelineManager/@recentLoad)[1]', 'float') as RecentLoad,
    t.value('(./PreConditionPipelineManager/pipeline/@recentLoad)[2]', 'float') as PipelineRecentLoad,
    t.value('(./PreConditionPipelineManager/pipeline/@running)[1]', 'bit') as PipelineRunning,
    t.value('(./PreConditionPipelineManager/pipeline/@startTime)[1]', 'datetime') as PipelineStartTime
from 
    @xml.nodes('processEngine') as a(t)

您可以使用任何XQuery表达式。有关详细信息，请参阅http://msdn.microsoft.com/en-us/library/ms189075.aspx。

或者您可以将表格列更改为xml类型而不是ntext，并使用如下查询：

select 
    xmlcolumn.value('(./processEngine/controller/@heartBeat)[1]', 'datetime') as HeartBeat,
    xmlcolumn.value('(./processEngine/PreConditionPipelineManager/@recentLoad)[1]', 'float') as RecentLoad,
    xmlcolumn.value('(./processEngine/PreConditionPipelineManager/pipeline/@recentLoad)[2]', 'float') as PipelineRecentLoad,
    xmlcolumn.value('(./processEngine/PreConditionPipelineManager/pipeline/@running)[1]', 'bit') as PipelineRunning,
    xmlcolumn.value('(./processEngine/PreConditionPipelineManager/pipeline/@startTime)[1]', 'datetime') as PipelineStartTime
from 
    xmltable

如何从＆＃34; ntext＆＃34;获取数据sql server中的列

1 个答案: