成人在线视频免费看,麻豆一区精品在线,中文字幕精品一区二区精品

SQL Server中新增加了XML.Modify()方法，分別為xml.modify(insert),xml.modify(delete),xml.modify(replace)對(duì)應(yīng)XML的插入，刪除和修改操作。
本文以下面XML為例，對(duì)三種DML進(jìn)行說(shuō)明：

復(fù)制代碼代碼如下:

declare @XMLVar XML;
SET @XMLVar= '

<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.Modify(Insert)語(yǔ)句介紹

A.利用as first,at last,before,after四個(gè)參數(shù)將元素插入指定的位置

復(fù)制代碼代碼如下:

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]');

結(jié)果集為：

復(fù)制代碼代碼如下:

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.將多個(gè)元素插入文檔中

復(fù)制代碼代碼如下:

--方法一：利用變量進(jìn)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]');

結(jié)果集為：

復(fù)制代碼代碼如下:

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.將屬性插入文檔中

復(fù)制代碼代碼如下:

--使用變量插入
declare @var nvarchar(10) = '變量插入'
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]');

結(jié)果集為：

復(fù)制代碼代碼如下:

1: <book category="ITPro" var="變量插入">
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.插入文本節(jié)點(diǎn)

復(fù)制代碼代碼如下:

set @XMLVar.modify(
'insert text{"at first"} as first)
into (/catalog[1]/book[1])'
SELECT @XMLVar.query('/catalog[1]/book[1]');

結(jié)果集為：

復(fù)制代碼代碼如下:

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：插入本文同樣具體 as first，as last，before，after四種選項(xiàng)，可以參考A中的使用方法

E.插入注釋節(jié)點(diǎn)

復(fù)制代碼代碼如下:

set @XMLVar.modify(
N'insert 
before (/catalog[1]/book[1]/title[1])' )
SELECT @XMLVar.query('/catalog[1]/book[1]');

結(jié)果集為：
1: <book category="ITPro">
2: 
3: <title>Windows Step By Step</title>
4: <author>Bill Zack</author>
5: <price>49.99</price>
6: </book>
注意插入注釋節(jié)點(diǎn)同樣具體 as first，as last，before，after四種選項(xiàng)，可以參考A中的使用方法

F.插入處理指令

復(fù)制代碼代碼如下:

set @XMLVar.modify(
'insert <?Program "Instructions.exe" ?>
before (/catalog[1]/book[1]/title[1])' )
SELECT @XMLVar.query('/catalog[1]/book[1]');

結(jié)果集為：
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>
注意插入處理指令同樣具體 as first，as last，before，after四種選項(xiàng)，可以參考A中的使用方法

G.根據(jù) if 條件語(yǔ)句進(jìn)行插入

復(fù)制代碼代碼如下:

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]');

結(jié)果集為：
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)語(yǔ)句介紹

復(fù)制代碼代碼如下:

--刪除屬性
set @XMLVar.modify('delete /catalog[1]/book[1]/@category')

--刪除節(jié)點(diǎn)
set @XMLVar.modify('delete /catalog[1]/book[1]/title[1]')

--刪除內(nèi)容
set @XMLVar.modify('delete /catalog[1]/book[1]/author[1]/text()')

--全部刪除
set @XMLVar.modify('delete /catalog[1]/book[2]')

SELECT @XMLVar.query('/catalog[1]');

結(jié)果集為：

復(fù)制代碼代碼如下:

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)語(yǔ)句介紹

復(fù)制代碼代碼如下:

--替換屬性
set @XMLVar.modify(N'replace value of(/catalog[1]/book[1]/@category)
with ("替換屬性")' )
--替換內(nèi)容
set @XMLVar.modify(N'replace value of(/catalog[1]/book[1]/author[1]/text()[1])
with("替換內(nèi)容")' )
--條件替換
set @XMLVar.modify(N'replace value of (/catalog[1]/book[2]/@category)
with(
if(count(/catalog[1]/book)>4) then
"條件替換1"
else
"條件替換2")' )

SELECT @XMLVar.query('/catalog[1]');
[code]
結(jié)果集為：
[code]
1: <catalog>
2: <book category="替換屬性">
3: <title>Windows Step By Step</title>
4: <author>替換內(nèi)容</author>
5: <price>49.99</price>
6: </book>
7: <book category="條件替換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>