(4.41)sql server如何把xml转换成表格数据?
【0】基本案例
declare @temp xml; set @temp='<root><note> <to>George</to> <from>John</from> <heading>Reminder</heading> <body>Dont forget the meeting!</body> </note> <note> <to>tom</to> <from>cat</from> <heading>test</heading> <body>test 123</body> </note> </root>'; select [to]=o.value('to[1]','nvarchar(500)'), [from]=o.value('from[1]','nvarchar(500)'), [heading]=o.value('heading[1]','nvarchar(500)'), [body]=o.value('body[1]','nvarchar(500)') from (select x=@temp) a cross apply x.nodes('root/note') x(o)
【XML与表格的互相转换】
【1】xml测试数据
<event name="sql_batch_completed" package="sqlserver" timestamp="2020-08-19T06:41:42.542Z"> <data name="cpu_time"> <value>141000</value> </data> <data name="duration"> <value>2947856</value> </data> <data name="physical_reads"> <value>12517</value> </data> <data name="logical_reads"> <value>10411</value> </data> <data name="writes"> <value>0</value> </data> <data name="row_count"> <value>0</value> </data> <data name="result"> <value>2</value> <text>Abort</text> </data> <data name="batch_text"> <value>SELECT * FROM match_nndouble </value> </data> <action name="task_time" package="sqlos"> <value>28573288</value> </action> <action name="database_name" package="sqlserver"> <value>test</value> </action> <action name="nt_username" package="sqlserver"> <value>WIN-OFM2A36CRMD\admin</value> </action> <action name="sql_text" package="sqlserver"> <value>SELECT * FROM match_nndouble </value> </action> <action name="transaction_id" package="sqlserver"> <value>0</value> </action> <action name="username" package="sqlserver"> <value>WIN-OFM2A36CRMD\admin</value> </action> </event>
【2】xml转换成表格形式查看
with d as ( SELECT CONVERT(XML,event_data) AS data from sys.Fn_xe_file_target_read_file(N'E:\dba_tools\eventlog\slow_query_0_132422809173040000.xel',NULL,NULL,NULL) ) select data.value('(/event/@timestamp)[1]','datetime') as record_time, --获取最上方标题行的内容 data.value('(/event/@name)[1]','nvarchar(128)') as operation_name, --获取最上方标题行的内容 --data.value('(/event/data[@name="cpu_time"]/value)[1]','int')/1000 as 'cpu_time(ms)',--获得 event=>data name=cpu_time 的 value data.value('(/event/data[@name="duration"]/value)[1]','int')/1000 as 'exec_time(ms)',--获得 event=>data name=duration 的 value --data.value('(/event/data[@name="physical_reads"]/value)[1]','int') as 'physical_reads',--获得 event=>data name=physical_reads 的 value --data.value('(/event/data[@name="logical_reads"]/value)[1]','int') as 'logical_reads',--获得 event=>data name=logical_reads 的 value --data.value('(/event/data[@name="writes"]/value)[1]','int') as 'writes',--获得 event=>data name=writes 的 value data.value('(/event/data[@name="row_count"]/value)[1]','int') as 'row_count',--获得 event=>data name=row_count 的 value data.value('(/event/data[@name="result"]/value)[1]','int') as 'result_flag',--获得 event=>data name=result 的 value data.value('(/event/data[@name="result"]/text)[1]','nvarchar(128)') as 'result_desc',--获得 event=>data name=result 的 text data.value('(/event/data[@name="batch_text"]/value)[1]','nvarchar(max)') as 'batch_text',--获得 event=>data name=batch_text 的 text data.value('(/event/action[@name="sql_text"]/value)[1]','nvarchar(4000)') as 'current_sql',--获得 event=>action name=sql_text 的 value --data.value('(/event/action[@name="task_time"]/value)[1]','int')/1000 as 'task_time(ms)',--获得 event=>action name=task_time 的 value data.value('(/event/action[@name="database_name"]/value)[1]','nvarchar(400)') as 'database_name',--获得 event=>action name=database_name 的 value data.value('(/event/action[@name="transaction_id"]/value)[1]','nvarchar(400)') as 'transaction_id',--获得 event=>action name=transaction_id 的 value data.value('(/event/action[@name="username"]/value)[1]','nvarchar(400)') as 'username',--获得 event=>action name=transaction_id 的 value data.value('(/event/action[@name="nt_username"]/value)[1]','nvarchar(400)') as 'nt_username'--获得 event=>action name=transaction_id 的 value from d
结果:
XML本身的5大操作
1.xml.exist
输入为XQuery表达式,返回0,1或是Null。0表示不存在,1表示存在,Null表示输入为空
2.xml.value
输入为XQuery表达式,返回一个SQL Server标量值
3.xml.query
输入为XQuery表达式,返回一个SQL Server XML类型流
4.xml.nodes
输入为XQuery表达式,返回一个XML格式文档的一列行集
5.xml.modify
使用XQuery表达式对XML的节点进行insert , update 和 delete 操作。
下面通过例子对上面的五种操作进行说明:
测试数据
declare @XMLVar xml = ' <catalog> <book category="ITPro"> <title>Windows Step By Step</title> <author>Bill Zack</author> <price>49.99</price> </book> <book category="Developer"> <title>Developing ADO .NET</title> <author>Andrew Brust</author> <price>39.93</price> </book> <book category="ITPro"> <title>Windows Cluster Server</title> <author>Stephen Forte</author> <price>59.99</price> </book> </catalog>'
1.xml.exist
select @XMLVar.exist('/catalog/book')-----返回1 select @XMLVar.exist('/catalog/book/@category')-----返回1 select @XMLVar.exist('/catalog/book1')-----返回0 set @XMLVar = null select @XMLVar.exist('/catalog/book')-----返回null
2.xml.value
select @XMLVar.value('/catalog[1]/book[1]','varchar(MAX)') select @XMLVar.value('/catalog[1]/book[2]/@category','varchar(MAX)') select @XMLVar.value('/catalog[2]/book[1]','varchar(MAX)')
结果集为:
Windows Step By StepBill Zack49.99 Developer NULL
3.xml.query
select @XMLVar.query('/catalog[1]/book') select @XMLVar.query('/catalog[1]/book[1]') select @XMLVar.query('/catalog[1]/book[2]/author') 结果集分别为: <book category="ITPro"> <title>Windows Step By Step</title> <author>Bill Zack</author> <price>49.99</price> </book> <book category="Developer"> <title>Developing ADO .NET</title> <author>Andrew Brust</author> <price>39.93</price> </book> <book category="ITPro"> <title>Windows Cluster Server</title> <author>Stephen Forte</author> <price>59.99</price> </book> <book category="ITPro"> <title>Windows Step By Step</title> <author>Bill Zack</author> <price>49.99</price> </book> <author>Andrew Brust</author>
4.xml.nodes
select T.c.query('.') as result from @XMLVar.nodes('/catalog/book') as T(c) select T.c.query('title') as result from @XMLVar.nodes('/catalog/book') as T(c)
结果集分别为:
<book category="ITPro"><title>Windows Step By Step</title><author>Bill ………… <book category="Developer"><title>Developing ADO .NET</title><author>Andrew ………… <book category="ITPro"><title>Windows Cluster Server</title><author>Stephen ………… <title>Windows Step By Step</title> <title>Developing ADO .NET</title> <title>Windows Cluster Server</title>
5.xml.modify
SQL Server 2005/2008增加了对XML数据的支持,同时也新增了几种操作XML的方法,本文主要以SQL Server 2008为例介绍如何对XML数据进行insert、update、delete。
SQL Server中新增加了XML.Modify()方法,分别为xml.modify(insert),xml.modify(delete),xml.modify(replace)对应XML的插入,删除和修改操作。
本文以下面XML为例,对三种DML进行说明:
declare @XMLVar xml = ' <catalog> <book category="ITPro"> <title>Windows Step By Step</title> <author>Bill Zack</author> <price>49.99</price> </book> <book category="Developer"> <title>Developing ADO .NET</title> <author>Andrew Brust</author> <price>39.93</price> </book> <book category="ITPro"> <title>Windows Cluster Server</title> <author>Stephen Forte</author> <price>59.99</price> </book> </catalog> '
深入 XML.Modify
1.XML.Modify(Insert)语句介绍
A.利用as first,at last,before,after 四个参数将元素插入指定的位置
set @XMLVar.modify( 'insert <first name="at first" /> as first into (/catalog[1]/book[1])') set @XMLVar.modify( 'insert <last name="at last"/> as last into (/catalog[1]/book[1])') set @XMLVar.modify( 'insert <before name="before"/> before (/catalog[1]/book[1]/author[1])') set @XMLVar.modify( 'insert <after name="after"/> after (/catalog[1]/book[1]/author[1])') SELECT @XMLVar.query('/catalog[1]/book[1]');
结果集为:
1: <book category="ITPro"> 2: <first name="at first" /> 3: <title>Windows Step By Step</title> 4: <before name="before" /> 5: <author>Bill Zack</author> 6: <after name="after" /> 7: <price>49.99</price> 8: <last name="at last" /> 9: </book>
B.将多个元素插入文档中
--方法一:利用变量进行插入
DECLARE @newFeatures xml; SET @newFeatures = N'; <first>one element</first> <second>second element</second>' SET @XMLVar.modify(' ) insert sql:variable("@newFeatures") into (/catalog[1]/book[1])'
--方法二:直接插入
set @XMLVar.modify(') insert (<first>one element</first>,<second>second element</second>) into (/catalog[1]/book[1]/author[1])' SELECT @XMLVar.query('/catalog[1]/book[1]');
结果集为:
1: <book category="ITPro"> 2: <title>Windows Step By Step</title> 3: <author>Bill Zack 4: <first>one element</first> 5: <second>second element</second> 6: </author> 7: <price>49.99</price> 8: <first>one element</first> 9: <second>second element</second> 10: </book>
C.将属性插入文档中
--使用变量插入
declare @var nvarchar(10) = '变量插入' set @XMLVar.modify( 'insert (attribute var {sql:variable("@var")})) into (/catalog[1]/book[1])'
--直接插入
set @XMLVar.modify( 'insert (attribute name {"直接插入"})) into (/catalog[1]/book[1]/title[1])'
--多值插入
set @XMLVar.modify( 'insert (attribute Id {"多值插入1"},attribute name {"多值插入2"}) ) into (/catalog[1]/book[1]/author[1])' SELECT @XMLVar.query('/catalog[1]/book[1]');
结果集为:
1: <book category="ITPro" var="变量插入"> 2: <title name="直接插入">Windows Step By Step</title> 3: <author Id="多值插入1" name="多值插入2">Bill Zack</author> 4: <price>49.99</price> 5: </book>
D.插入文本节点
set @XMLVar.modify( 'insert text{"at first"} as first) into (/catalog[1]/book[1])' SELECT @XMLVar.query('/catalog[1]/book[1]');
结果集为:
1: <book category="ITPro"> 2: at first 3: <title>Windows Step By Step</title> 4: <author>Bill Zack</author> 5: <price>49.99</price> 6: </book>
注意:插入本文同样具体 as first,as last,before,after四种选项,可以参考A中的使用方法
E.插入注释节点
set @XMLVar.modify( 'insert <!--插入评论-->) before (/catalog[1]/book[1]/title[1])' SELECT @XMLVar.query('/catalog[1]/book[1]');
结果集为:
1: <book category="ITPro"> 2: <!--插入评论--> 3: <title>Windows Step By Step</title> 4: <author>Bill Zack</author> 5: <price>49.99</price> 6: </book>
注意插入注释节点同样具体 as first,as last,before,after四种选项,可以参考A中的使用方法
F.插入处理指令
set @XMLVar.modify( 'insert <?Program "Instructions.exe" ?>) before (/catalog[1]/book[1]/title[1])' SELECT @XMLVar.query('/catalog[1]/book[1]'); 结果集为: 1: <book category="ITPro"> 2: <?Program "Instructions.exe" ?> 3: <title>Windows Step By Step</title> 4: <author>Bill Zack</author> 5: <price>49.99</price> 6: </book>
注意插入处理指令同样具体 as first,as last,before,after四种选项,可以参考A中的使用方法
G.根据 if 条件语句进行插入
set @XMLVar.modify( 'insert ) if (/catalog[1]/book[1]/title[2]) then text{"this is a 1 step"} else ( text{"this is a 2 step"} ) into (/catalog[1]/book[1]/price[1])' SELECT @XMLVar.query('/catalog[1]/book[1]');
结果集为:
1: <book category="ITPro"> 2: <title>Windows Step By Step</title> 3: <author>Bill Zack</author> 4: <price>49.99this is a 2 step</price> 5: </book>
2.XML.Modify(delete)语句介绍
--删除属性
set @XMLVar.modify('delete /catalog[1]/book[1]/@category')
--删除节点
set @XMLVar.modify('delete /catalog[1]/book[1]/title[1]')
--删除内容
set @XMLVar.modify('delete /catalog[1]/book[1]/author[1]/text()')
--全部删除
set @XMLVar.modify('delete /catalog[1]/book[2]')
SELECT @XMLVar.query('/catalog[1]');
结果集为:
1: <catalog>
2: <book>
3: <author />
4: <price>49.99</price>
5: </book>
6: <book category="ITPro">
7: <title>Windows Cluster Server</title>
8: <author>Stephen Forte</author>
9: <price>59.99</price>
10: </book>
11: </catalog>
3.XML.Modify(replace)语句介绍
--替换属性
set @XMLVar.modify('replace value of(/catalog[1]/book[1]/@category))
with ("替换属性")'
--替换内容
set @XMLVar.modify('replace value of(/catalog[1]/book[1]/author[1]/text()[1]))
with("替换内容")'
--条件替换
set @XMLVar.modify('replace value of (/catalog[1]/book[2]/@category))
with(
if(count(/catalog[1]/book)>4) then
"条件替换1"
else
"条件替换2")'
SELECT @XMLVar.query('/catalog[1]');
结果集为:
1: <catalog>
2: <book category="替换属性">
3: <title>Windows Step By Step</title>
4: <author>替换内容</author>
5: <price>49.99</price>
6: </book>
7: <book category="条件替换2">
8: <title>Developing ADO .NET</title>
9: <author>Andrew Brust</author>
10: <price>39.93</price>
11: </book>
12: <book category="ITPro">
13: <title>Windows Cluster Server</title>
14: <author>Stephen Forte</author>
15: <price>59.99</price>
16: </book>
17: </catalog>