讀取XML節點屬性沒有在SQL Server查詢

Question

我已經XML存儲到數據庫中與不同的標記名稱，但相同的屬性名稱中使用節點名稱：

<book Category="Hobbies And Interests" PropertyName="C#" CategoryID="44" /> 
<sport Category="Hobbies And Interests" PropertyName="Cricket" CategoryID="46" /> 

這只是兩個例子，但是標籤名稱可以是任何東西。我想讀取所有節點的「PropertyName」屬性。

可能嗎？如果是的話，請任何人指導我。

Answer 1

declare @xml xml 

set @xml = '<book Category="Hobbies And Interests" PropertyName="C#" CategoryID="44" /> 
<sport Category="Hobbies And Interests" PropertyName="Cricket" CategoryID="46" />' 

select T.c.value('@PropertyName', 'varchar(100)') 
from @xml.nodes('/*') T(c) 

如果用戶希望可以有沒有屬性名屬性的元素，你可以使用：

select T.c.value('@PropertyName', 'varchar(100)') 
from @xml.nodes('/*[@PropertyName]') T(c) 

如果你還期望元素可以嵌套，你可以使用：

select T.c.value('@PropertyName', 'varchar(100)') 
from @xml.nodes('//*[@PropertyName]') T(c) 

Answer 2

DECLARE @MyTable TABLE(
    ID INT IDENTITY(1,1) PRIMARY KEY, 
    XmlCol XML NOT NULL 
); 
INSERT @MyTable(XmlCol) 
VALUES (N'<book Category="Hobbies And Interests" PropertyName="C#" CategoryID="44" />'); 
INSERT @MyTable(XmlCol) 
VALUES (N'<sport Category="Hobbies And Interests" PropertyName="Cricket" CategoryID="46" />'); 
INSERT @MyTable(XmlCol) 
VALUES (N'<CocoJambo PropertyName="Aircraft carrier" Category="Hobbies And Interests"> <CocoJamboChild PropertyName="Airplane"/> </CocoJambo>'); 
INSERT @MyTable(XmlCol) 
VALUES (N'<sport CategoryID="CocoJamboID" />'); 

SELECT a.*, 
     b.Node.value('(.)','NVARCHAR(100)') AS PropertyName_Value 
FROM @MyTable a 
-- OUTER APPLY or CROSS APLLY 
OUTER APPLY a.XmlCol.nodes('//@*[local-name(.)="PropertyName"]') b(Node); 

：如果你想從所有節點讀取 PropertyName值

嘗試這種解決方案

結果：

ID   XmlCol         PropertyName_Value 
----------- ----------------------------------------- ------------------ 
1   <book Category="Hobbies And Interes ... C# 
2   <sport Category="Hobbies And Intere ... Cricket 
3   <CocoJambo PropertyName="Aircraft c ... Aircraft carrier 
3   <CocoJambo PropertyName="Aircraft c ... Airplane 
4   <sport CategoryID="CocoJamboID" />  NULL 

但是，如果你想顯示有至少一個PropertyName屬性XML framents所有行，那麼你可以嘗試：

SELECT a.* 
FROM @MyTable a 
WHERE a.XmlCol.exist('//@*[local-name(.)="PropertyName"]')=1; 

結果：

ID   XmlCol 
----------- ---------------------------------------------------------------------------------- 
1   <book Category="Hobbies And Interests" PropertyName="C#" CategoryID="44" /> 
2   <sport Category="Hobbies And Interests" PropertyName="Cricket" CategoryID="46" /> 
3   <CocoJambo PropertyName="Aircraft carrier" Category="Hobbies And Interests"><CocoJ ...